Red Hat Enterprise Linux 7
7.2 Release Notes
Release Notes for Red Hat Enterprise Linux 7.2
Red Hat Customer Content Services
Red Hat Enterprise Linux 7 7.2 Release Notes
Release Notes for Red Hat Enterprise Linux 7.2
Red Hat Custo mer Co ntent Services
rhel-no [email protected] m
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Abstract
The Release No tes pro vide high-level co verage o f the impro vements and additio ns that have
been implemented in Red Hat Enterprise Linux 7.2 and do cument kno wn pro blems in this
release. Fo r detailed do cumentatio n o n all changes to Red Hat Enterprise Linux fo r the 7.2
update, refer to Errata o n the Red Hat Custo mer Po rtal.
T able of Cont ent s
T able of Contents
. .reface
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⁠C ro s s c hannel p ac kag e d ep end enc y imp ro vements
⁠R ELRO p ro tec tio n no w p ro p erly ap p lied when req ues ted
⁠M o re d iag no s tic info rmatio n and a renamed p lug -in fo r s o s rep o rt
⁠E nab le virtio netwo rk d evic e renaming
⁠S up p o rt fo r DIF/DIX (T10 PI) o n s p ec ified hard ware
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⁠Id entity Manag ement s ets up a o ne-way trus t b y d efault
14
⁠o p enld ap reb as e to vers io n 2.4.40
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⁠C ac he authentic atio n in SSSD
⁠S SSD enab les UID and G ID map p ing o n ind ivid ual c lients
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⁠S SSD c an no w d eny SSH ac c es s to lo c ked ac c o unts
⁠T he s ud o utility no w c ap ab le o f verifying c o mmand c hec ks um
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⁠S SSD s mart c ard s up p o rt
⁠S up p o rt fo r multip le c ertific ate p ro files and us er c ertific ates
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⁠P as s wo rd Vault
⁠K erb ero s HTTPS p ro xy in Id entity Manag ement
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⁠B ac kg ro und refres h o f c ac hed entries
⁠C ac hing fo r initg ro up s o p eratio ns
⁠N eg o tiate authentic atio n s treamlined with mo d _auth_g s s ap i
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⁠U s er life-c yc le manag ement c ap ab ilities
⁠S CEP s up p o rt in c ertmo ng er
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⁠A p ac he mo d ules fo r Id M no w fully s up p o rted
⁠N SS rais es minimum ac c ep ted key s treng th values
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⁠N SS enab les TLS vers io n 1.1 and 1.2 b y d efault
⁠E CDSA c ertific ates are no w s up p o rted
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⁠O p enLDAP auto matic ally c ho o s es the NSS d efault c ip her s uites
⁠C o nfig uring an Id M s erver to b e a trus t ag ent no w s up p o rted
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16
⁠A uto mated mig ratio n fro m WinSync to trus ts no w s up p o rted
⁠M ulti-s tep p ro mp ting fo r o ne-time and lo ng -term p as s wo rd s
⁠L PK s c hema fo r O p enLDAP no w availab le in the LDIF fo rmat
⁠C yrus c an authentic ate to AD and Id M s ervers ag ain
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⁠S SSD s up p o rts o verrid ing auto matic ally d is c o vered AD s ite
⁠S up p o rt fo r SAML ECP has b een ad d ed
⁠T he winb ind d s ervic e no lo ng er lis ts g ro up memb ers hip s in its d efault c o nfig uratio n
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⁠s ys temd and p ac emaker no w c o o rd inate c o rrec tly d uring s ys tem s hutd o wn
19
⁠T he p c s res o urc e mo ve and p c s res o urc e b an c o mmand s no w d is p lay a warning mes s ag e to c larify
the c o mmand s ' b ehavio r
19
⁠N ew c o mmand to mo ve a Pac emaker res o urc e to its p referred no d e
⁠S imp lified metho d fo r c o nfig uring fenc ing fo r red und ant p o wer s up p lies in a c lus ter
⁠N ew --p o rt-as -ip o p tio n fo r fenc ing ag ents
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⁠tail --fo llo w no w wo rks p ro p erly o n files o n Veritas Clus tered file s ys tem (VXFS)
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⁠T he d d c o mmand no w c ap ab le o f s ho wing trans fer p ro g res s
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1
7 .2 Release Not es
⁠T he d d c o mmand no w c ap ab le o f s ho wing trans fer p ro g res s
⁠Imp ro ved wait times in lib c url
⁠T he lib c url lib rary no w imp lements a no n-b lo c king SSL hand s hake
⁠G DB o n IBM Po wer Sys tems no lo ng er fails when ac c es s ing the s ymb o l tab le
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⁠n s c d up d ated to auto matic ally relo ad c o nfig uratio n d ata
⁠T he d lo p en lib rary func tio n no lo ng er c ras hes o n rec urs ive c alls
⁠T he o p erf to o l no w rec o g niz es s tatic hug e p ag e id entifiers
⁠r s ync -X no w wo rks c o rrec tly
⁠S ub vers io n exec utab les no w b uilt with full RELRO d ata
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21
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⁠T he thread extens io n in TCL no w wo rks c o rrec tly
⁠A ES c ip her s uites c an b e exp lic itly enab led o r d is ab led fo r TLS
⁠O p enJDK 7 no w s up p o rts ECC
⁠A BRT is no w ab le to s ave a c o re_b ac ktrac e file ins tead o f a who le c o red ump
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⁠S ec urity features ad d ed to the Pytho n s tand ard lib rary
⁠N ew g lo b al s etting s fo r SSL/TLS c ertific ate verific atio n in the Pytho n s tand ard lib rary
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⁠G NO ME reb as e to vers io n 3.14
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⁠T he ib us -g tk2 p ac kag e no w up d ates the immo d ules .c ac he file
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⁠g fs 2-utils reb as e to vers io n 3.1.8
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⁠G FS2 no w p revents us ers fro m exc eed ing their q uo tas
⁠X FS reb as e to vers io n 4.1
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⁠c ifs reb as e to vers io n 3.17
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⁠C hang es in NFS in Red Hat Enterp ris e Linux 7.2
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⁠O SA-Exp res s 5s c ard s s up p o rt in q ethq o at
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⁠Fixed netwo rk s etup in initrd if netwo rk c o nfig uratio n is p ro vid ed in Kic ks tart
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⁠A nac o nd a no w s up p o rts c reating c ac hed lo g ic al vo lumes
⁠Imp ro ved s o rting o f G RUB2 b o o t menu
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⁠A nac o nd a no w p ro p erly reverts d is k ac tio ns when d is k s elec tio n c hang es
⁠Imp ro ved d etec tio n o f d evic e-map p er d is k names
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⁠Fixed hand ling o f PReP Bo o t d uring p artitio ning
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⁠E FI p artitio ns o n RAID1 d evic es
⁠T ext mo d e ins tallatio n no lo ng er c ras hes d uring netwo rk c o nfig uratio n
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⁠R es c ue mo d e s c reens o n IBM Sys tem z are no lo ng er c ut o ff
⁠O p enSCAP ad d -o n in Anac o nd a
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⁠A nac o nd a no lo ng er times o ut when waiting fo r a Kic ks tart file o n a CD o r DVD
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...........
⁠M ultip le CPU s up p o rt in kd ump o n AMD6 4 and Intel 6 4 s ys tems
⁠S up p o rt fo r kp atc h
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30
⁠T he SHMMAX and SHMALL kernel p arameters returned to d efault values
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⁠T rans p arent hug e p ag es no lo ng er c aus e memo ry c o rrup tio n
⁠S CSI LIO reb as e
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⁠m aked ump file no w s up p o rts the new s ad ump fo rmat rep res enting up to 16 TB o f p hys ic al memo ry
⁠R emo ving o r up g rad ing kernel no lo ng er d is p lays a warning
30 30
2
⁠N ew p ac kag e: lib evd ev
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⁠T uned c an no w run in no -d aemo n mo d e
⁠N ew p ac kag e: tuned -p ro files -realtime
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31
⁠S CSI erro r mes s ag es c an no w b e interp reted c o mfo rtab ly
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T able of Cont ent s
⁠l ib ATA s ub s ys tem and d rivers up d ated
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⁠FCo E and DCB have b een up g rad ed
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⁠p erf reb as e to vers io n 4.1
⁠S up p o rt fo r TPM 2.0
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⁠turb o s tat no w p ro vid es c o rrec t o utp ut
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⁠turb o s tat no w s up p o rts Intel Xeo n v5 p ro c es s o rs
⁠the z s wap to o l makes us e o f the z p o o l API
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⁠T he /p ro c /p id /c md line file leng th is no w unlimited
⁠S up p o rt fo r d ma_rmb and d ma_wmb no w p ro vid ed
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⁠q ib HCA d river c o nnec tio n
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⁠Inc reas e in memo ry limit
⁠N ew variab les fo r d rac ut
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⁠i 40 e and i40 evf no w fully s up p o rted
⁠S NMP no w c o rrec tly o b eys the c lientad d r d irec tive o ver IPv6
34
34
⁠tc p d ump s up p o rts -J, -j, and --time-s tamp -p rec is io n o p tio ns
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⁠T CP/IP reb as e to vers io n 3.18
⁠N etwo rkManag er lib res wan reb as e to vers io n 1.0 .6
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⁠N etwo rkManag er no w s up p o rts s etting the MTU o f a b o nd ed interfac e
34
⁠N etwo rkManag er no w valid ates IPv6 Ro uter Ad vertis ement MTU o p tio ns b efo re ap p lying them
⁠IPv6 Privac y extens io ns no w enab led b y d efault
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35
⁠T he c o ntro l-c enter Netwo rk Panel no w d is p lays WiFi d evic e c ap ab ilities
35
⁠N etwo rkManag er no w g rac efully hand les ro ute c o nflic ts when multip le interfac es p o int to the s ame
g ateway
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⁠Fix fo r netwo rk b lac ko ut with multiho med c o nnec tio ns
35
⁠N ew o p tio n to p revent Netwo rkManag er fro m o verrid ing ip ro ute ad d
⁠Fix fo r leg ac y netwo rk.s ervic e erro rs when Carrier Do wn is d etec ted o n s o me hard ware
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35
⁠N etwo rkManag er no w s up p o rts Wake O n Lan
⁠Imp ro ved s up p o rt fo r firewalld z o nes with VPN c o nnec tio ns
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⁠Fair Q ueue p ac ket s c hed uler no w s up p o rted
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⁠A d d ed s up p o rt fo r trans mit c o ales c ing
⁠Imp ro ved netwo rk frame rec eiving p erfo rmanc e
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⁠S ig nific antly imp ro ved p erfo rmanc e o f ro ute lo o kup s
⁠N etwo rk Names p ac e s up p o rt fo r Virtual Interfac es
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⁠D o c ker and LXC c o ntainers c an no w read net.ip v4.ip _lo c al_p o rt_rang e
36
⁠Imp ro ved rep o rting o f auto c o nfig ured IPv6 ro utes b y the ' ip ' to o l
⁠D ual-s tac k s o c ket o p tio ns are no w c o rrec tly exp o rted
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36
⁠D ata Center TCP No w Sup p o rted
36
⁠P er Ro ute Co ng es tio n Co ntro l
36
⁠Imp ro ved Co ng es tio n Wind o w hand ling fo r TCP Cub ic and Reno when us ing G RO
⁠T CP Pac ing is no w s up p o rted
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37
⁠S up p o rt fo r b o th c lient and s erver TFO
37
⁠M itig atio n o f TCP ACK lo o p s
37
⁠M inimal s up p o rt fo r s ec o nd ary end p o ints with nf_c o nntrac k_p ro to _s c tp
37
⁠A F_UNIX imp lementatio n reb as ed
⁠K ernel tunneling s up p o rt reb as ed to up s tream
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⁠A d d ed s up p o rt fo r c ro s s ing netwo rk names p ac es to G RE
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⁠Imp ro ved p erfo rmanc e when running Virtual Mac hine Traffic o ver VXLAN
37
⁠Imp ro ved o fflo ad ing fo r VLAN frames rec eived in a VXLAN o r fro m G RE tunnels
37
⁠Imp ro ved p erfo rmanc e o f O p en vSwitc h tunneling
⁠Imp ro ved IPs ec Hand ling
37
37
⁠Inc lus io n o f VTI6 s up p o rt inc lud ing netns c ap ab ilities
38
⁠D efault value o f nf_c o nntrac k_b uc kets inc reas ed
38
3
7 .2 Release Not es
⁠D efault value o f nf_c o nntrac k_b uc kets inc reas ed
38
⁠Imp ro vements in memo ry us ag e fo r ip tab les o n larg e SMP mac hines
38
⁠N etwo rk b o nd ing d river up d ated
⁠K ernel netlink interfac es fo r b o nd ing and 8 0 2.3ad (LACP)
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38
⁠Imp ro vements in p erfo rmanc e fo r mac tap and mac vtap with VLANs
38
⁠Imp ro ved ethto o l netwo rk q uerying
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⁠G SSAPI key-exc hang e alg o rithms c an no w b e s elec tively d is ab led
39
⁠S ELinux p o lic y fo r Red Hat G lus ter Sto rag e has b een ad d ed
⁠o p ens c ap reb as e to vers io n 1.2.5
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⁠s c ap -s ec urity-g uid e reb as e to vers io n 0 .1.25
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⁠T he Erro rPo lic y d irec tive is no w valid ated
40
⁠C UPS no w d is ab les SSLv3 enc ryp tio n b y d efault
40
⁠c up s no w allo ws und ers c o re in p rinter names
40
⁠U nneed ed d ep end enc y remo ved fro m the tftp -s erver p ac kag e
⁠T he d ep rec ated /etc /s ys c o nfig /c o nman file has b een remo ved
40
40
⁠m o d _ns s reb as e to vers io n 1.0 .11
40
⁠T he vs ftp d d aemo n no w s up p o rts DHE and ECDHE c ip her s uites
40
⁠P ermis s io ns c an no w b e s et fo r files up lo ad ed with s ftp
40
⁠L DAP q ueries us ed b y s s h-ld ap -help er c an no w b e ad jus ted
⁠A new c reateo ld d ir d irec tive in the lo g ro tate utility
41
41
⁠E rro r mes s ag es fro m /etc /c ro n.d aily/lo g ro tate are no lo ng er red irec ted to /d ev/null
41
⁠S EED and IDEA b as ed alg o rithms res tric ted in mo d _s s l
41
⁠A p ac he HTTP Server no w s up p o rts UPN
41
⁠T he mo d _d av lo c k d atab as e is no w enab led b y d efault in the mo d _d av_fs mo d ule
⁠m o d _p ro xy_ws tunnel no w s up p o rts Web So c kets
41
41
⁠A Tuned p ro file o p timiz ed fo r O rac le d atab as e s ervers has b een inc lud ed
42
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⁠D M reb as e to vers io n 4.2
43
⁠M ultiq ueue I/O s c hed uling with b lk-mq
43
⁠N ew d elay_watc h_c hec ks and d elay_wait_c hec ks o p tio ns in the multip ath.c o nf file
⁠N ew c o nfig _d ir o p tio n in the multip ath.c o nf file
43
43
⁠N ew d ms tats c o mmand to d is p lay and manag e I/O s tatis tic s fo r reg io ns o f d evic es that us e the
d evic e-map p er d river
44
⁠L VM Cac he
44
⁠N ew LVM/DM c ac he p o lic y
44
⁠L VM s ys temID
⁠N ew lvmp o lld d aemo n
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44
⁠E nhanc ements to LVM s elec tio n c riteria
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⁠T he d efault maximum numb er o f SCSI LUNs is inc reas ed
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4
⁠P o werTO P no w res p ec ts us er-d efined rep o rt file names
46
⁠A mend ed yum-c o nfig -manag er c o mmand s
⁠N ew s earc h-d is ab led -rep o s p lug -in fo r yum
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46
⁠A c q uiring hyp ervis o r d ata in p arallel
46
⁠Filtering fo r hyp ervis o rs rep o rted b y virt-who
46
⁠Imp ro ved vis ualiz atio n o f ho s t-to -g ues t as s o c iatio n
46
⁠virt-who o utp ut d is p layed as ho s t names
⁠P re-filled virt-who c o nfig uratio n file
46
47
⁠E nhanc ed p ro xy c o nnec tio n o p tio ns
47
T able of Cont ent s
⁠E nhanc ed p ro xy c o nnec tio n o p tio ns
47
⁠S ub s c rip tio n Manag er no w s up p o rts s ys lo g
47
⁠S ub s c rip tio n Manag er is no w p art o f Initial Setup
47
⁠S ub s c rip tio n Manag er no w d is p lays the s erver URL when reg is tering o n a c o mmand line
47
⁠M anag e Rep o s ito ries d ialo g in Sub s c rip tio n Manag er is no w mo re res p o ns ive
⁠R eaR no w wo rks als o o n interfac es o ther than eth0
47
47
. .hapt
⁠C
. . . .er
. .1. 6. .. Virt
. . . ualiz
. . . . .at. ion
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4. 8. . . . . . . . . .
⁠q emu-kvm s up p o rts virtual mac hine s hutd o wn trac e events
48
⁠Intel MPX exp o s ed to the g ues t
48
⁠G ues t memo ry d ump extrac tio n fro m the q emu-kvm c o re
48
⁠virt-v2v is fully s up p o rted
⁠V irtualiz atio n o n IBM Po wer Sys tems
48
48
⁠H yp er-V TRIM s up p o rt
48
⁠K VM s up p o rt fo r tc mallo c
48
⁠S elec tive d is k c o p ying d uring d o main live mig ratio n
48
⁠D evic es that us e RMRRs are no w exc lud ed fro m IO MMU API d o mains
⁠N ew p ac kag e: WALinuxAg ent
49
49
. .hapt
⁠C
. . . .er
. .1. 7. .. At
. . omic
. . . . .Host
. . . . .and
. . . .Cont
. . . .ainers
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
...........
⁠ Red Hat Enterp ris e Linux Ato mic Ho s t
50
. .hapt
⁠C
. . . .er
. .1. 8. .. Red
. . . . Hat
. . . .Soft
. . . .ware
. . . . Collect
. . . . . . ions
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
...........
. .art
⁠P
. . .II.. .T.echnology
. . . . . . . . . .Previews
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
...........
. .hapt
⁠C
. . . .er
. .1. 9. .. Aut
. . . hent
. . . . .icat
. . .ion
. . . and
. . . . Int
. . .eroperabilit
. . . . . . . . . .y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
...........
⁠U s e o f AD and LDAP s ud o p ro vid ers
53
⁠D NSSEC availab le as Tec hno lo g y Preview in Id entity Manag ement
53
⁠N unc Stans event framewo rk availab le fo r Direc to ry Server
⁠B ro ws er fo r the JSO N-RPC API in Id M is availab le
53
53
⁠N ew p ac kag es : ip s ilo n
53
. .hapt
⁠C
. . . .er
. .2. 0. .. Clust
. . . . .ering
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
...........
⁠S up p o rt fo r c lufter, a to o l fo r trans fo rming and analyz ing c lus ter c o nfig uratio n fo rmats
54
. .hapt
⁠C
. . . .er
. .2. 1. .. File
. . . .Syst
. . . .ems
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
...........
⁠O verlayFS
55
⁠S up p o rt fo r NFSv4 c lients with flexib le file layo ut
55
⁠B trfs file s ys tem
⁠p NFS Blo c k Layo ut Sup p o rt
55
56
. .hapt
⁠C
. . . .er
. .2. 2. .. Hardware
. . . . . . . . .Enablement
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
...........
⁠R untime Ins trumentatio n fo r IBM Sys tem z
57
⁠L SI Sync ro CS HA-DAS ad ap ters
57
. .hapt
⁠C
. . . .er
. .2. 3.
. . Kernel
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
...........
⁠T he c riu to o l
58
⁠U s er names p ac e
⁠L PAR Watc hd o g fo r IBM Sys tem z
58
58
⁠i 40 evf hand les b ig res ets
58
⁠S up p o rt fo r Intel® O mni-Path Arc hitec ture kernel d river
58
⁠S up p o rt fo r Diag 0 c o n IBM Sys tem z
58
⁠10 G b E Ro CE Exp res s feature fo r RDMA
⁠z EDC c o mp res s io n o n IBM Sys tem z
58
59
. .hapt
⁠C
. . . .er
. .2. 4. .. Net
. . . working
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6. 0. . . . . . . . . .
5
7 .2 Release Not es
⁠C is c o us NIC d river
60
⁠C is c o VIC kernel d river
60
⁠T rus ted Netwo rk Co nnec t
60
⁠S R-IO V func tio nality in the q lc nic d river
60
. .hapt
⁠C
. . . .er
. .2. 5.
. . St
. . orage
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6. 1. . . . . . . . . .
⁠M ulti-q ueue I/O s c hed uling fo r SCSI
61
⁠Imp ro ved LVM lo c king infras truc ture
61
⁠T arg etd p lug -in fro m the lib Sto rag eMg mt API
61
⁠D IF/DIX
61
. .hapt
⁠C
. . . .er
. .2. 6. .. Virt
. . . ualiz
. . . . .at. ion
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6. 2. . . . . . . . . .
⁠N es ted virtualiz atio n
62
⁠T he virt-p 2v to o l
⁠U SB 3.0 s up p o rt fo r KVM g ues ts
62
62
⁠V irtIO -1 s up p o rt
62
. .art
⁠P
. . .III.
. . Device
. . . . . . Drivers
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6. 3. . . . . . . . . .
. .hapt
⁠C
. . . .er
. .2. 7. .. St
. . orage
. . . . . .Driver
. . . . . Updat
. . . . . .es
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6. 4. . . . . . . . . .
. .hapt
⁠C
. . . .er
. .2. 8. .. Net
. . . work
. . . . .Driver
. . . . . .Updat
. . . . . es
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6. 5. . . . . . . . . .
. .hapt
⁠C
. . . .er
. .2. 9. .. G
. .raphics
. . . . . . .Driver
. . . . . and
. . . . Miscellaneous
. . . . . . . . . . . . . Driver
. . . . . .Updat
. . . . . es
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6. 6. . . . . . . . . .
. .hapt
⁠C
. . . .er
. .30
. . .. Deprecat
. . . . . . . . ed
. . .Funct
. . . . .ionalit
. . . . . .y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6. 7. . . . . . . . . .
⁠Wind o ws g ues t virtual mac hine s up p o rt limited
67
⁠D ep rec ated Devic e Drivers
67
. .art
⁠P
. . .IV.
. . Known
. . . . . . .Issues
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7. 0. . . . . . . . . .
. .hapt
⁠C
. . . .er
. .31
. . .. G
. .eneral
. . . . . Updat
. . . . . .es
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7. 1. . . . . . . . . .
⁠ The TAB key d o es no t exp and $ PWD b y d efault
71
⁠U p g rad ing fro m Red Hat Enterp ris e Linux 6 may fail o n IBM Po wer Sys tems
⁠T he /etc /o s -releas e file c o ntains o utd ated info rmatio n after s ys tem up g rad e
71
71
. .hapt
⁠C
. . . .er
. .32
. . .. Aut
. . . hent
. . . . icat
. . . .ion
. . . and
. . . .Int
. . eroperabilit
. . . . . . . . . . .y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7. 2. . . . . . . . . .
⁠K erb ero s tic ket req ues ts are refus ed fo r s ho rt lifetimes
⁠R ep lic atio n fro m a Red Hat Enterp ris e Linux 7 mac hine to a Red Hat Enterp ris e Linux 6 mac hine
fails
72
⁠A harmles s erro r mes s ag e is lo g g ed o n SSSD s tartup
⁠D NS z o nes with rec ently g enerated DNSSEC keys are no t s ig ned p ro p erly
72
72
⁠T he o ld realmd vers io n is s tarted when up d ating realmd while it is running
⁠i p a-s erver-ins tall and ip a-rep lic a-ins tall d o no t valid ate their o p tio ns
⁠U p g rad ing the ip a p ac kag es fails if the req uired o p ens s l vers io n is no t ins talled
72
72
73
72
. .hapt
⁠C
. . . .er
. .33.
. . .Compiler
. . . . . . . . and
. . . .T. ools
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7. 4. . . . . . . . . .
⁠M ultip le b ug s when b o o ting fro m SAN o ver FCo E
⁠V alg rind c anno t run p ro g rams b uilt ag ains t an earlier vers io n o f O p en MPI
74
74
⁠S ynthetic func tio ns g enerated b y G CC c o nfus e Sys temTap
⁠S ELinux AVC g enerated when ABRT c o llec ts b ac ktrac es
⁠G DB keep s watc hp o ints ac tive even after rep o rting them as hit
74
74
74
⁠B o o ting fails us ing g rub aa6 4.efi
⁠M PX feature in G CC req uires Red Hat Develo p er To o ls et vers io n o f the lib mp x lib rary
75
75
. .hapt
⁠C
. . . .er
. .34
. . .. Deskt
. . . . . op
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7. 6. . . . . . . . . .
⁠B ro ken p yg o b jec t3 p ac kag e d ep end enc ies p revent up g rad e fro m Red Hat Enterp ris e Linux 7.1
⁠B uild req uirements no t d efined c o rrec tly fo r Emac s
76
6
76
T able of Cont ent s
⁠B uild req uirements no t d efined c o rrec tly fo r Emac s
⁠E xternal d is p lay is s ues when c o mb ining lap to p un/d o c k and s us p end
76
⁠E mac s s o metimes terminates unexp ec ted ly when us ing the up arro w o n ARM
76
76
76
. .hapt
⁠C
. . . .er
. .35.
. . .Inst
. . . allat
. . . . ion
. . . .and
. . . Boot
. . . . .ing
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7. 7. . . . . . . . . .
⁠Ins tallatio n fails with a trac eb ac k when s p ec ifying % p ac kag es --no b as e --no c o re in a Kic ks tart file
77
⁠Ins tallatio n c an no t p ro c eed if a ro o t p as s wo rd s p ec ified in Kic ks tart d o es no t p as s p o lic y
req uirements
77
⁠R es c ue mo d e fails to d etec t and mo unt ro o t vo lume o n Btrfs
⁠Wro ng wind o w title in Initial Setup
⁠R eins talling o n an FBA DASD o n IBM Sys tem z c aus es the ins taller to c ras h
77
77
77
⁠H yp erPAV alias es are no t availab le after ins tallatio n o n IBM Sys tem z
⁠G enerated anac o nd a-ks .c fg file o n IBM Sys tem z c an no t b e us ed to reins tall the s ys tem
77
78
⁠P o s s ib le Netwo rkManag er erro r mes s ag e d uring ins tallatio n
⁠P ac kag e lib o c rd ma is mis s ing fro m the InfiniBand Sup p o rt p ac kag e g ro up
⁠Ins uffic ient s iz e o f the /b o o t p artitio n may p revent the s ys tem fro m up g rad ing
78
78
78
⁠Ins tallatio n o n multip ath d evic es fails if o ne o r mo re d is ks are mis s ing a lab el
⁠S tatic IPv4 c o nfig uratio n in Kic ks tart is o verwritten if a ho s t name is d efined in % p re s c rip t
79
79
⁠U s ing the realm c o mmand in Kic ks tart c aus es the ins taller to c ras h
⁠Ins taller b uilt-in help is no t up d ated d uring s ys tem up g rad e
⁠Inc o rrec t o rd ering o f b o o t menu entries g enerated b y g rub b y
79
79
80
⁠U s ing multip le d river up d ate imag es at the s ame time o nly ap p lies the las t o ne s p ec ified
⁠Ins taller c ras hes when it d etec ts LDL-fo rmatted DASDs
80
80
⁠K ernel p anic o n reb o o t after up g rad ing kernel and red hat-releas e p ac kag es
⁠Initial Setup may s tart in text mo d e even if a g rap hic al enviro nment is ins talled
⁠L inks to no n-ro o t file s ys tems in /lib / and /lib 6 4/ are remo ved b y ld c o nfig .s ervic e
80
81
81
⁠D aemo ns us ing IPC terminate unexp ec ted ly after up d ate to Red Hat Enterp ris e Linux 7.2
81
. .hapt
⁠C
. . . .er
. .36
. . .. Kernel
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8. 2. . . . . . . . . .
⁠S o me ext4 file s ys tems c anno t b e res iz ed
82
⁠R ep eated c o nnec tio n lo s s with iSER-enab led iSCSI targ ets
⁠Ins taller d o es no t d etec t Fib re Channel o ver Ethernet d is ks o n EDD s ys tems
⁠N UMA b alanc ing d o es no t wo rk o p timally und er c ertain c irc ums tanc es
82
82
82
⁠P SM2 MTL d is ab led to avo id c o nflic ts b etween PSM and PSM2 APIs
⁠P erfo rmanc e p ro b lem o f the p erf utility
82
83
⁠q lc nic fails to ens laved b y b o nd ing
⁠Ins tallatio n fails o n s o me 6 4-b it ARM Ap p lied Mic ro c o mp uters
⁠l ib virt manag ement o f VFIO d evic es c an lead to ho s t c ras hes
83
83
83
⁠Ins tallatio n us ing iSCSI and IPv6 hang s fo r 15 minutes
⁠i 40 e NIC freez e
83
83
⁠i 40 e is is s uing WARN_O N
⁠n etp rio _c g ro up s no t mo unted at b o o t
83
83
. .hapt
⁠C
. . . .er
. .37
. . .. Net
. . . working
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8. 5. . . . . . . . . .
⁠T imeo ut p o lic y no t enab led in Red Hat Enterp ris e Linux 7.2 kernel
85
⁠V erific atio n o f s ig natures us ing the MD5 has h alg o rithm is d is ab led in Red Hat Enterp ris e Linux 7
85
. .hapt
⁠C
. . . .er
. .38
. . .. St
. . orage
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8. 6. . . . . . . . . .
⁠N o s up p o rt fo r thin p ro vis io ning o n to p o f RAID in a c lus ter
⁠When us ing thin-p ro vis io ning , it is p o s s ib le to lo s e b uffered writes to the thin-p o o l if it reac hes
c ap ac ity
86
86
. .hapt
⁠C
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. .39
. . .. Syst
. . . . em
. . . and
. . . .Subscript
. . . . . . . . .ion
. . .Management
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8. 7. . . . . . . . . .
⁠N o n-wo rking Bac k b utto n in the Sub s c rip tio n Manag er ad d -o n fo r Initial Setup
87
⁠virt-who fails to c hang e ho s t-to -g ues t as s o c iatio n to the Cand lep in s erver
87
7
7 .2 Release Not es
⁠virt-who fails to c hang e ho s t-to -g ues t as s o c iatio n to the Cand lep in s erver
87
⁠R eaR fails to c reate an ISO o n IBM Sys tem z
⁠R eaR s up p o rts o nly g rub d uring s ys tem rec o very
87
87
. .hapt
⁠C
. . . .er
. .4. 0. .. Virt
. . . ualiz
. . . . .at. ion
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8. 8. . . . . . . . . .
⁠P ro b lematic G RUB 2 navig atio n with KVM
⁠R es iz ing G UID Partitio n Tab le (G PT) d is ks o n Hyp er-V g ues ts c aus es p artitio n tab le erro rs
⁠B rid g e c reatio n with virs h ifac e-b rid g e fails
88
88
88
⁠Q EMU-emulated CAC s mart c ard s inc o mp atib le with Ac tivClient s o ftware
⁠virtio -win VFD files d o no t c o ntain Wind o ws 10 d rivers
88
88
⁠M ig rated g ues ts d o no t d is p lay the b o o t menu o n the s erial c o ns o le
88
. .ppendix
⁠A
. . . . . . . A.
. . Component
. . . . . . . . . . . Versions
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9. 0. . . . . . . . . .
. .ppendix
⁠A
. . . . . . . B.
. . .Revision
. . . . . . . .Hist
. . . ory
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9. 1. . . . . . . . . .
8
⁠P reface
Preface
Red Hat Enterprise Linux minor releases are an aggregation of individual enhancement, security,
and bug fix errata. The Red Hat Enterprise Linux 7.2 Release Notes document describes the major
changes made to the Red Hat Enterprise Linux 7 operating system and its accompanying
applications for this minor release, as well as known problems and a complete list of all currently
available Technology Previews.
Capabilities and limits of Red Hat Enterprise Linux 7 as compared to other versions of the system are
available in the Red Hat Knowledgebase article available at https://access.redhat.com/articles/rhellimits.
For information regarding the Red Hat Enterprise Linux life cycle, refer to
https://access.redhat.com/support/policy/updates/errata/.
9
7 .2 Release Not es
Chapter 1. Architectures
Red Hat Enterprise Linux 7.2 is available as a single kit on the following architectures: ⁠ [1]
64-bit AMD
64-bit Intel
IBM POWER7+ and POWER8 (big endian) ⁠ [2]
IBM POWER8 (little endian) ⁠ [3]
IBM System z ⁠ [4]
[1] No te that the Red Hat Enterp ris e Linux 7.2 ins tallatio n is s up p o rted o nly o n 6 4-b it hard ware. Red Hat
Enterp ris e Linux 7.2 is ab le to run 32-b it o p erating s ys tems , inc lud ing p revio us vers io ns o f Red Hat
Enterp ris e Linux, as virtual mac hines .
[2] Red Hat Enterp ris e Linux 7.2 (b ig end ian) is c urrently s up p o rted as a KVM g ues t o n Red Hat
Enterp ris e Virtualiz atio n fo r Po wer and o n Po werVM.
[3] Red Hat Enterp ris e Linux 7.2 (little end ian) is c urrently s up p o rted as a KVM g ues t o n Red Hat
Enterp ris e Virtualiz atio n fo r Po wer, o n Po werVM and Po werNV (b are metal).
[4] No te that Red Hat Enterp ris e Linux 7.2 s up p o rts IBM z Enterp ris e 19 6 hard ware o r later; IBM Sys tem
z 10 mainframe s ys tems are no lo ng er s up p o rted and will no t b o o t Red Hat Enterp ris e Linux 7.2.
10
⁠P art I. New Feat ures
⁠Part I. New Features
This part describes new features and major enhancements introduced in Red Hat Enterprise Linux
7.2.
11
7 .2 Release Not es
Chapter 2. General Updates
Cross channel package dependency improvement s
Yum has been enhanced to prompt the end user to search disabled package repositories on the
system when a package dependency error occurs. This change will allow users to quickly resolve
dependency errors by first checking all known channels for the missing package dependency.
To enable this functionality, execute yum upd ate yum subscri pti o n-manag er prior to
upgrading your machine to Red Hat Enterprise Linux 7.2.
Please see the System and Subscription Management chapter for further details on the
implementation of this feature.
RELRO prot ect ion now properly applied when request ed
Previously, binary files started by the system loader would, in some cases, lack the Relocation ReadOnly (RELRO) protection even though this had been explicitly requested when the application was
built. This was due to a miscommunication between the static linker and the system loader. The
underlying source code of the linker has been adjusted to ensure that it makes it possible for the
loader to apply the RELRO protection, thus restoring the security feature for applications.
Applications and all dependent object files, archives, and libraries built with an alpha or beta version
of binutils should be rebuilt to correct this defect. This update fixes the issue on the AMD 64, Intel 64,
64-bit PowerPC, and 64-bit ARM architectures.
More diagnost ic informat ion and a renamed plug-in for sosreport
The sosreport tool has been enhanced to collect process-related information from various
applications, including ptp, lastlog, and ethtool. As a part of this change, the startup plug-in has
been renamed to servi ces in order to better communicate its function.
Enable virt io net work device renaming
This update adds a new persistent naming scheme for the virtio driver, which enables virtio network
device renaming. To enable this feature in Red Hat Enterprise Linux 7.2, add the net. i fnames= 1
kernel parameter while booting.
Support for DIF/DIX (T 10 PI) on specified hardware
SCSI T10 D IF/D IX is fully supported in Red Hat Enterprise Linux 7.2, provided that the hardware
vendor has qualified it and provides full support for the particular HBA and storage array
configuration. D IF/D IX is not supported on other configurations, it is not supported for use on the
boot device, and it is not supported on virtualized guests.
At the current time, the following vendors are known to provide this support.
FUJITSU supports D IF and D IX on:
EMULEX 16G FC HBA:
EMULEX LPe16000/LPe16002, 10.2.254.0 BIOS, 10.4.255.23 FW, with:
FUJITSU ETERNUS D X100 S3, D X200 S3, D X500 S3, D X600 S3, D X8100 S3, D X8700 S3,
D X8900 S3, D X200F, D X60 S3
12
⁠Chapt er 2 . G eneral Updat es
QLOGIC 16G FC HBA:
QLOGIC QLE2670/QLE2672, 3.28 BIOS, 8.00.00 FW, with:
FUJITSU ETERNUS D X100 S3, D X200 S3, D X500 S3, D X600 S3, D X8100 S3, D X8700 S3,
D X8900 S3, D X200F, D X60 S3
Note that T10 D IX requires database or some other software that provides generation and verification
of checksums on disk blocks. No currently supported Linux file systems have this capability.
EMC supports D IF on:
EMULEX 8G FC HBA:
LPe12000-E and LPe12002-E with firmware 2.01a10 or later, with:
EMC VMAX3 Series with Enginuity 5977; EMC Symmetrix VMAX Series with Enginuity
5876.82.57 and later
EMULEX 16G FC HBA:
LPe16000B-E and LPe16002B-E with firmware 10.0.803.25 or later, with:
EMC VMAX3 Series with Enginuity 5977; EMC Symmetrix VMAX Series with Enginuity
5876.82.57 and later
QLOGIC 16G FC HBA:
QLE2670-E-SP and QLE2672-E-SP, with:
EMC VMAX3 Series with Enginuity 5977; EMC Symmetrix VMAX Series with Enginuity
5876.82.57 and later
Please refer to the hardware vendor's support information for the latest status.
Support for D IF/D IX remains in Tech Preview for other HBAs and storage arrays.
13
7 .2 Release Not es
Chapter 3. Authentication and Interoperability
Ident it y Management set s up a one-way t rust by default
The i pa trust-ad d command now configures a one-way trust by default. One-way trusts enable
users and groups in Active D irectory (AD ) to access resources in Identity Management (IdM) but not
the other way around. Previously, the default trust configured by running i pa trust-ad d was a
two-way trust.
IdM still allows the administrator to set up a two-way trust by adding the --two -way= true option to
i pa trust-ad d .
o penl d ap rebase t o version 2.4 .4 0
The openldap packages have been upgraded to upstream version 2.4.40, which provides a number of
bug fixes and one enhancement over the previous version. Notably, the ORD ERING matching rules
have been added to the ppo l i cy attribute type descriptions. Among the fixed bugs are: The server
no longer terminates unexpectedly when processing SRV records, and missing o bjectC l ass
information has been added, which enables the user to modify the front-end configuration by
standard means.
Cache aut hent icat ion in SSSD
Authentication against cache without a reconnection attempt is now available in SSSD even in
online mode. Authenticating directly against the network server repeatedly could cause excessive
application latency, which could make the login process overly time-consuming.
SSSD enables UID and GID mapping on individual client s
It is now possible to map users to a different UID and GID on specific Red Hat Enterprise Linux clients
through client-side configuration by using SSSD . This client-side override possibility can resolve
problems caused by UID and GID duplication or ease transition from a legacy system that previously
used different ID mapping.
Note that the overrides are stored in the SSSD cache; removing the cache therefore also removes the
overrides.
SSSD can now deny SSH access t o locked account s
Previously, when SSSD used OpenLD AP as its authentication database, users could authenticate
into the system successfully with an SSH key even after the user account was locked. The
l d ap_access_o rd er parameter now accepts the ppo l i cy value, which can deny SSH access to
the user in the described situation. For more information about using ppo l i cy, see the
l d ap_access_o rd er description in the sssd-ldap(5) manual page.
T he sudo ut ilit y now capable of verifying command checksum
The configuration of the sudo utility can now store the checksum of a command or script that is being
permitted. When the command or script is run again, the checksum is compared to the stored
checksum to verify that nothing has changed. If the command or binary is modified, the sudo utility
refuses to run the command or logs a warning. This functionality makes it possible to correctly
devolve responsibility and problem-solving activities if an incident occurs.
14
⁠Chapt er 3. Aut hent icat ion and Int eroperabilit y
SSSD smart card support
SSSD now supports smart cards for local authentication. With this feature, the user can use a smart
card to log on to the system using a text-based or graphical console, as well as local services such
as the sudo service. The user places the smart card into the reader and provides the user name and
the smart card PIN at the login prompt. If the certificate on the smart card is verified, the user is
successfully authenticated.
Note that SSSD does not currently enable the user to acquire a Kerberos ticket using a smart card.
To obtain a Kerberos ticket, the user is still required to authenticate using the kinit utility.
Support for mult iple cert ificat e profiles and user cert ificat es
Identity Management now supports multiple profiles for issuing server and other certificates instead
of only supporting a single server certificate profile. The profiles are stored in the D irectory Server
and shared between IdM replicas.
In addition, the administrator can now issue certificates to individual users. Previously, it was only
possible to issue certificates to hosts and services.
Password Vault
A new feature to allow secure central storage of private user information, such as passwords and
keys has been added to Identity Management. Password Vault is built on top of the Public Key
Infrastructure (PKI) Key Recovery Authority (KRA) subsystem.
Kerberos HT T PS proxy in Ident it y Management
A Key D istribution Center (KD C) proxy function, interoperable with the Microsoft Kerberos KD C Proxy
Protocol (MS-KKD CP) implementation, is now available in Identity Management and allows clients to
access the KD C and kpasswd services by using HTTPS. System administrators can now expose the
proxy at their network edge by a simple HTTPS reverse proxy without the need to set up and manage
a dedicated application.
Background refresh of cached ent ries
SSSD now allows cached entries to be updated out-of-band in the background. Prior to this update,
when the validity of cached entries expired, SSSD fetched them from the remote server and stored
them in the database anew, which could be time consuming. With this update, entries are returned
instantly because the back end keeps them updated at all times. Note that this causes a higher load
on the server because SSSD downloads the entries periodically instead of only upon request.
Caching for i ni tg ro ups operat ions
The SSSD fast memory cache now supports the i ni tg ro ups operations, which enhances the
speed of initgroups processing and improves the performance of some applications, for example
GlusterFS and sl api -ni s.
Negot iat e aut hent icat ion st reamlined wit h mo d _auth_g ssapi
Identity Management now uses the mo d _auth_g ssapi module, which uses GSSAPI calls instead of
direct Kerberos calls used by the previously used mo d _auth_kerb module.
15
7 .2 Release Not es
User life-cycle management capabilit ies
The user life-cycle management gives the administrator a greater degree of control over activating
and deactivating user accounts. The administrator can now provision new user accounts by adding
them to a stage area without fully activating them, activate inactive user accounts to make them fully
operational, or deactivate user accounts without completely deleting them from the database.
User life-cycle management capabilities bring significant benefits to large IdM deployments. Note that
users can be added to the stage area also directly from a standard LD AP client, using direct LD AP
operations. Previously, IdM only supported managing users using IdM command-line tools or the
IdM web UI.
SCEP support in certmo ng er
The certmo ng er service has been updated to support the Simple Certificate Enrollment Protocol
(SCEP). It is now possible to issue a new certificate and renew or replace existing certificates over
SCEP.
Apache modules for IdM now fully support ed
The following Apache modules for Identity Management (IdM), added as Technology Preview in Red
Hat Enterprise Linux 7.1, are now fully supported: mo d _authnz_pam, mo d _l o o kup_i d enti ty, and
mo d _i ntercept_fo rm_submi t. The Apache modules can be used by external applications to
achieve tighter interaction with IdM beyond simple authentication.
NSS raises minimum accept ed key st rengt h values
The Network Security Services (NSS) library in Red Hat Enterprise Linux 7.2 no longer accepts D iffieHellman (D H) key exchange parameters smaller than 768 bits, nor RSA and D SA certificates with key
sizes less than 1023 bits. Raising the minimum accepted key strength values prevents attacks
exploiting known security vulnerabilities such as Logjam (CVE-2015-4000) and FREAK (CVE-20150204).
Note that attempts to connect to a server by using keys weaker than the new minimum values now fail,
even though such connections worked in previous versions of Red Hat Enterprise Linux.
NSS enables T LS version 1.1 and 1.2 by default
Applications using protocol versions that NSS enables by default now additionally support the TLS
version 1.1 and TLS version 1.2 protocols.
ECDSA cert ificat es are now support ed
Applications that use the default NSS cipher list now support connections to servers that use Elliptic
Curve D igital Signature Algorithm (ECD SA) certificates.
OpenLDAP aut omat ically chooses t he NSS default cipher suit es
OpenLD AP clients now automatically choose the Network Security Services (NSS) default cipher
suites for communication with the server. It is no longer necessary to maintain the default cipher
suites manually in the OpenLD AP source code.
Configuring an IdM server t o be a t rust agent now support ed
16
⁠Chapt er 3. Aut hent icat ion and Int eroperabilit y
Identity Management (IdM) distinguishes two types of IdM master servers: trust controllers and trust
agents. Trust controllers run all the services required for establishing and maintaining a trust; trust
agents only run services required to provide resolution of users and groups from trusted Active
D irectory forests to IdM clients enrolled with these IdM servers.
By default, running the i pa-ad trust-i nstal l command sets up the IdM server as a trust
controller. To configure another IdM server to be a trust agent, pass the --ad d -ag ents option to
i pa-ad trust-i nstal l .
Aut omat ed migrat ion from WinSync t o t rust s now support ed
The new i pa-wi nsync-mi g rate utility enables seamless migration from synchronization-based
integration using WinSync to integration based on Active D irectory (AD ) trust. The utility
automatically migrates all users synchronized using WinSync from a specified AD forest. Previously,
migration from synchronization to trust could only be performed manually using ID views.
For more information about i pa-wi nsync-mi g rate, see the ipa-winsync-migrate(1) man page.
Mult i-st ep prompt ing for one-t ime and long-t erm passwords
When using a one-time password (a token) together with a long-term password to log in, the user is
prompted for both passwords separately. This results in better user experience when using one-time
passwords as well as a safer long-term password extraction, which allows long-term password
caching to be used for offline authentication.
LPK schema for OpenLDAP now available in t he LDIF format
LD IF is the new default format for the OpenLD AP import schema, and the openssh-ldap package now
provides the LD AP Public Key (LPK) schema in the LD IF format as well. Therefore, administrators can
directly import the LD IF schema when setting up public-key authentication based on LD AP.
Cyrus can aut hent icat e t o AD and IdM servers again
An upstream release of the cyrus-sasl packages introduced a non-backward compatible change that
prevented Cyrus from authenticating against older SASL implementations. Consequently, Red Hat
Enterprise Linux 7 was not able to authenticate to Active D irectory (AD ) and Red Hat Enterprise Linux
6 Identity Management (IdM) servers. The upstream change has been reverted and Cyrus can now
authenticate to AD and IdM servers as expected.
SSSD support s overriding aut omat ically discovered AD sit e
The Active D irectory (AD ) D NS site to which the client connects is discovered automatically by
default. However, the default automatic search might not discover the most suitable AD site in certain
setups. In such situations, you can now define the D NS site manually using the ad _si te parameter
in the [d o mai n/NAME] section of the /etc/sssd /sssd . co nf file.
Support for SAML ECP has been added
The lasso packages have been rebased to version 2.5.0 and the mod_auth_mellon packages have
been rebased to version 0.11.0 in order to add support for Security Assertion Markup Language
(SAML) Enhanced Client or Proxy (ECP). SAML ECP is an alternative SAML profile that allows nonbrowser-based Single Sign On (SSO).
17
7 .2 Release Not es
T he winbindd service no longer list s group memberships in it s default
configurat ion
The wi nbi nd d service in Samba version 4.2.0 and later no longer lists group memberships for
display purposes. In some situations, such as in environments with trusted domains, it was not
always possible to provide this information reliably. To prevent the risk of providing inaccurate
information, the default wi nbi nd d configuration has been changed to wi nbi nd expand g ro ups
= 0 , which disables the previous behavior. Note that some commands, such as the g etent g ro up
command, previously relied on this functionality and might not behave as before.
18
⁠Chapt er 4 . Clust ering
Chapter 4. Clustering
syst emd and pacemaker now coordinat e correct ly during syst em shut down
Previously, systemd and pacemaker did not coordinate correctly during system shutdown, which
caused pacemaker resources not to be terminated properly. With this update, pacemaker is ordered
to stop before dbus and other systemd services that pacemaker started. This allows both pacemaker
and the resources that pacemaker manages to shut down properly.
T he pcs reso urce mo ve and pcs reso urce ban commands now display a warning
message t o clarify t he commands' behavior
The pcs reso urce mo ve command and the pcs reso urce ban commands create location
constraints that that effectively ban the resource from running on the current node until the constraint
is removed or until the constraint lifetime expires. This behavior had previously not been clear to
users. These commands now display a warning message explaining this behavior, and the help
screens and documentation for these commands have been clarified.
New command t o move a Pacemaker resource t o it s preferred node
After a Pacemaker resource has moved, either due to a failover or to an administrator manually
moving the node, it will not necessarily move back to its original node even after the circumstances
that caused the failover have been corrected. You can now use the pcs reso urce rel o cate run
command to move a resource to its preferred node, as determined by current cluster status,
constraints, location of resources and other settings. You can also use the pcs reso urce
rel o cate sho w command to display migrated resources. For information on these commands, see
the High Availability Add-On Reference.
Simplified met hod for configuring fencing for redundant power supplies in a
clust er
When configuring fencing for redundant power supplies, you must ensure that when the power
supplies are rebooted both power supplies are turned off before either power supply is turned back
on. If the node never completely loses power, the node may not release its resources. This opens up
the possibility of nodes accessing these resources simultaneously and corrupting them.
Prior to Red Hat Enterprise Linux 7.2, you needed to explicitly configure different versions of the
devices which used either the 'on' or 'off' actions. Since Red Hat Enterprise Linux 7.2, it is now only
required to define each device once and to specify that both are required to fence the node.
For information on configuring fencing for redundant power supplies, see the Fenci ng :
C o nfi g uri ng ST O NIT H chapter of the High Availability Add-On Reference manual.
New --port -as-ip opt ion for fencing agent s
Fence agents used only with single devices required complex configuration in pacemaker. It is now
possible to use the --po rt-as-i p option to enter the IP address in the po rt option.
19
7 .2 Release Not es
Chapter 5. Compiler and Tools
t ail --follow now works properly on files on Verit as Clust ered file syst em
(VXFS)
Veritas Clustered file system (VXFS) is a remote file system, and for remote file systems, tai l cannot
use i no ti fy functionality for --fo l l o w mode. Veritas Clustered file system has now been added
to the list of remote file systems, for which polling mode is used instead of i no ti fy. tai l -fo l l o w can now work properly even when used on files on VXFS.
T he dd command now capable of showing t ransfer progress
The d d command, which is used for copying files by bytes, now provides the status= pro g ress
option for showing the progress of the transfer. This is especially useful for transfers of large files
because it allows the user to estimate the time left and detect potential issues with the transfer.
Improved wait t imes in libcurl
The l i bcurl library used an unnecessarily long blocking delay for actions with no active file
descriptors, even for short operations. This meant that some actions, such as resolving a host name
using /etc/ho sts, took an artificially long time to complete. The blocking code in l i bcurl has
now been modified so that the initial delay is short, and gradually increases until an event occurs.
Fast l i bcurl operations now complete more quickly.
T he libcurl library now implement s a non-blocking SSL handshake
Previously, the l i bcurl library did not implement a non-blocking SSL handshake, which negatively
affected performance of applications based on the l i bcurl multi API. To solve this problem, the
non-blocking SSL handshake has been implemented in l i bcurl , and the l i bcurl multi API now
immediately returns the control back to the application whenever it cannot read or write data from or
to the underlying network socket.
GDB on IBM Power Syst ems no longer fails when accessing t he symbol t able
Previously, GD B on 64-bit IBM Power Systems incorrectly deallocated an important variable that
held the symbol table for the binary being debugged, which caused a segmentation fault when GD B
tried to access that symbol table. To solve this issue, this specific variable has been made persistent,
and GD B can now access the needed information later during the debugging session, without
reading an invalid memory region.
nscd updat ed t o aut omat ically reload configurat ion dat a
This update of Name Server Caching D aemon (nscd) adds a system of inotify-based monitoring and
stat-based backup monitoring for nscd configuration files, so that nscd now correctly detects
changes to its configuration and reloads the data. This prevents nscd from returning stale data.
T he dlopen library funct ion no longer crashes on recursive calls
Previously, a defect in the library function d l o pen could cause recursive calls to this function to
crash or abort with a library assertion. Recursive calls are possible if a user-provided mal l o c
implementation calls d l o pen.
The implementation is now reentrant, and recursive calls no longer crash or abort with an assertion.
20
⁠Chapt er 5. Compiler and T ools
T he operf t ool now recogniz es st at ic huge page ident ifiers
Previously, when profiling performance of Java just-in-time (JIT) compiled code with static huge
pages enabled, OProfile's operf command recorded a large number of event samples to anonymous
memory (in anon_hugepage) instead of to the appropriate Java method. With this update, operf
recognizes the static huge page identifiers and correctly maps samples to Java methods when using
statically allocated huge pages.
rsync -X now works correct ly
Previously, the rsync tool changed the file ownership after, not before, setting security attributes. As
a consequence, the security attributes on the target were missing, and running the rsync -X
command did not work correctly under certain circumstances. With this update, the order of the
operations has been switched, and rsync now changes the ownerships before setting the security
attributes. As a result, the security attributes are present as expected in the described situation.
Subversion execut ables now built wit h full RELRO dat a
The executables supplied with the subversion package are now built with fully read-only relocation
data (RELRO), which provides protection against some types of memory corruption attacks. As a
result, it will be harder to successfully exploit Subversion if future vulnerabilities are discovered.
T he t hread ext ension in T CL now works correct ly
Previously, the threading support in the Tool Command Language (TCL) was not implemented
optimally. If the fork() call was used together with thread extension enabled in the TCL interpreter, the
process could become unresponsive. Because of that, the TCL interpreter and the TK application
were previously shipped with the thread extension disabled. As a consequence, third-party
applications depending on threaded TCL or TK did not work correctly. A patch has been implemented
to fix this bug, and TCL and TK now have the thread extension enabled by default.
AES cipher suit es can be explicit ly enabled or disabled for T LS
With the updated curl packages, it is possible to explicitly enable or disable new Advanced
Encryption Standard (AES) cipher suites to be used for the TLS protocol.
OpenJDK 7 now support s ECC
With this update, OpenJD K 7 supports Elliptic Curve Cryptography (ECC) and the associated ciphers
for TLS connections. ECC is in most cases preferable to older cryptographic solutions for making
secure network connections.
ABRT is now able t o save a core_backt race file inst ead of a whole coredump
ABRT can now be configured to generate a backtrace without writing a coredump file to the disk. This
can save time when working with processes which have allocated large blocks of memory. This
feature can be enabled by setting the C reateC o reBacktrace option to yes and the
SaveFul l C o re option to no in the /etc/abrt/pl ug i ns/C C pp. co nf file.
Securit y feat ures added t o t he Pyt hon st andard library
21
7 .2 Release Not es
A number of security enhancements, which are described in the 466 Python Enhancent Proposal
(http://legacy.python.org/dev/peps/pep-0466/), have been backported to the Python standard library.
The security enhancements include, for example, new features in the ssl module, such as support
for Server Name Indication (SNI) as well as support for new TLSv1.x protocols, new hash algorithms
in the hashl i b mo d ul e, and much more.
New global set t ings for SSL/T LS cert ificat e verificat ion in t he Pyt hon
st andard library
New options have been added that allow users to globally enable or disable SSL/TLS certificate
verification in the HTTP clients (such as urllib, httplib, or xmlrpclib) of the Python standard library.
The options are described in the 493 Python Enhancement Proposal
(https://www.python.org/dev/peps/pep-0493/). The default value is to not verify certificates. For
details, see https://access.redhat.com/articles/2039753.
22
⁠Chapt er 6 . Deskt op
Chapter 6. Desktop
GNOME rebase t o version 3.14
The G NO ME D eskto p has been upgraded to upstream version 3.14 (with some minor additions from
3.16), which includes new features and a number of enhancements. Namely:
Red Hat Enterprise Linux 7.2 adds G NO ME So ftware, a new way to install and manage software on
the user's system based on a yum backend. GNOME PackageKit remains to be the default updater for
GNOME (also installed by default). With G NO ME So ftware, the user manages an integrated place
for software related tasks, such as browsing, installing and removing applications, and viewing and
installing software updates.
On the Top Bar, the newly-named System Status Menu groups together all of the indicators and
applets otherwise accessed individually – brightness slider, improved airplane mode, connecting to
Wi-Fi networks, Bluetooth, Volume, and so on – into one coherent and compact menu. Regarding WiFi, GNOME 3.14 provides improved support for Wi-Fi hotspots. When connecting to a Wi-Fi portal
that requires authentication, GNOME now automatically shows the login page as a part of the
connection process.
The default key combination for locking the screen has been changed. The previous default shortcut
C trl + Al t+ L has been replaced by the Super key+ L key combination.
The new design of the g ed i t text editor incorporates all of previous features into a more compact
interface, which gives more space for work. Use of popovers for selecting the document format and
tab width is more efficient compared to the previous use of dialogs and menus. Consolidated sidebar
controls also give more space for content while retaining the original functionality. Other notable
improvements include new shortcuts for opening the last closed tab with C trl + Shi ft+ T and for
changing case.
Nauti l us, the GNOME file manager, now uses the Shi ft+ C trl + Z key combination, not C trl + Y ,
for the red o operation. Also, a header bar, instead of a toolbar, is now used.
GNOME 3.14 includes a reimagined Vi d eo s application. Modern in style, the new version allows the
user to browse videos on the computer as well as online video channels. Vi d eo s also includes a
redesigned playback view. This provides a more streamlined experience than the earlier version:
floating playback controls hide when the user does not need them, and the fullscreen playback view
also has a new more refined look.
Evi nce features improved accessibility for reading PD F files. The new version of the document
viewer uses a header bar to give more space to your documents. When it is launched without a
document being specified, Evi nce also shows a useful overview of your recent documents. The
latest Evi nce version also includes Hi g h R eso l uti o n D i spl ay Suppo rt and enhanced
accessibility, with links, images and form fields all being available from assistive technologies.
The new version of GNOME Weather application makes use of GNOME's new geolocation framework
to automatically show the weather for your current location, and a new layout provides an effective
way to read weather forecasts.
This release also brings improved support for comments in Li breO ffi ce - import and export of
nested comments in the OD F, D OC, D OCX and RTF filters, printing comments in margins, and
formatting all comments.
The GNOME application for virtual and remote machines, Bo xes, introduces snapshots. Bo xes now
provide automatic downloading, running multiple boxes in separate windows, and user interface
improvements, including improved fullscreen behavior and thumbnails.
23
7 .2 Release Not es
The GNOME Hel p documentation viewer has been redesigned to be consistent with other GNOME 3
applications. Help now uses a header bar, has an integrated search function, and bookmarking
interface.
G T K+ 3.14 includes a number of bug fixes and enhancements, such as automatic loading of menus
from resources, multi-selection support in G tkLi stBo x, property bindings in G tkBui l d er files,
support for drawing outside a widget's allocation (gtk_widget_set_clip()), new transition types in
GtkStack, and file loading and saving with G tkSo urceVi ew. In addition, G T K+ now provides
support for gesture interaction. With 3.14, the majority of common multitouch gestures are available
for use in GTK+ applications, such as tap, drag, swipe, pinch, and rotate. Gestures can be added to
existing GTK+ applications using G tkG esture.
A GNOME Shell Extension, Lo o ki ng G l ass Inspecto r, has obtained a number of features for
developers: showing all methods, classes, and so on in a namespace upon inspection, object
inspector history expansion, or copying Lo o ki ng G l ass results as strings, and passing through
events to gnome-shell.
The Hi g h R eso l uti o n D i spl ay Suppo rt feature has been extended to include all the key
aspects of the core GNOME 3 experience, including the Activities Overview, animations in the
Activities Overview along with new window animations, Top Bar, lock screen and system dialogs.
As far as GNOME Extensions are concerned, this release introduces support for alternative dock
positioning, including the bottom side of the screen, in Si mpl e D o ck, a dock for the Gnome Shell.
T he ibus-gt k2 package now updat es t he immodules.cache file
Previously, the upd ate-g tk-i mmo d ul es script searched for a no longer existing /etc/g tk2. 0 /$ho st directory. Consequently, the post-installation script of the ibus-gtk2 package failed and
exited without creating or updating the cache. The post-installation script has been changed to
replace upd ate-g tk-i mmo d ul es with g tk-q uery-i mmo d ul es-2. 0 -BIT S, and the problem no
longer occurs.
24
⁠Chapt er 7 . File Syst ems
Chapter 7. File Systems
gfs2-ut ils rebase t o version 3.1.8
The gfs2-utils package has been rebased to version 3.1.8, which provides important fixes and a
number of enhancements:
* The performance of the fsck. g fs2, mkfs. g fs2, and g fs2_ed i t utilities has been improved.
* The fsck. g fs2 utility now performs better checking of journals, the jindex, system inodes, and the
inode 'goal' values.
* The g fs2_jad d and g fs2_g ro w utilities are now separate programs instead of symlinks to
mkfs. g fs2.
* The test suite and related documentation have been improved.
* The package no longer depends on Perl.
GFS2 now prevent s users from exceeding t heir quot as
Previously, GFS2 only checked quota violations after the completion of operations, which could
result in users or groups exceeding their allotted quotas. This behavior has been fixed, and GFS2
now predicts how many blocks an operation would allocate and checks if allocating them would
violate quotas. Operations that would result in quota violations are disallowed, and users thus never
exceed their allotted quotas.
XFS rebase t o version 4 .1
XFS has been upgraded to upstream version 4.1 including minor bug fixes, refactorings, reworks of
certain internal mechanisms, such as logging, pcpu accounting, and new mmap locking. On top of
the upstream changes, this update extends the rename() function to add cross-rename (a symmetric
variant of rename()) and whiteout handling.
cifs rebase t o version 3.17
The CIFS module has been upgraded to upstream version 3.17, which provides various minor fixes
and new features for Server Message Block (SMB) 2 and 3: SMB version 2.0, 2.1, 3.0, and 3.0.2.
Note that using the Linux kernel CIFS module with SMB protocol 3.1.1 is currently experimental and
the functionality is unavailable in kernels provided by Red Hat.
Changes in NFS in Red Hat Ent erprise Linux 7.2
Fallocate support allows preallocation of files on the server. The SEEK_HOLE and SEEK_D ATA
extensions to the fseek() function make it possible to locate holes or data quickly and efficiently. Red
Hat Enterprise Linux 7.2 also adds support for flexible file layout on NFSv4 clients described in the
Technology Previews section.
25
7 .2 Release Not es
Chapter 8. Hardware Enablement
OSA-Express5s cards support in qet hqoat
Support for OSA-Express5s cards was added to the qethqoat tool, part of the s390utils package, in
Red Hat Enterprise Linux 7.1 as a Technology Preview. This enhancement update provides full
support of the extended serviceability of network and card setups for OSA-Express5s cards.
26
⁠Chapt er 9 . Inst allat ion and Boot ing
Chapter 9. Installation and Booting
Fixed net work set up in init rd if net work configurat ion is provided in Kickst art
Previously, the installer was failing to set up or reconfigure network interfaces in i ni trd , if these
interfaces were defined in Kickstart files. This could cause the installation to fail and enter emergency
mode if network access was required by other commands in the Kickstart file.
This issue is now resolved and Anaconda now properly handles network configuration from Kickstart
files in i ni trd , early in the boot process.
Anaconda now support s creat ing cached logical volumes
The installer now supports creating cached LVM logical volumes and installing the system onto
those volumes.
Currently, this approach is only supported in Kickstart. To create a cached logical volume, use the
new --cachepvs= , --cachesi ze= , and --cachemo d e= options of the l o g vo l Kickstart
command.
See the Red Hat Enterprise Linux 7 Installation Guide for detailed information about these new
options.
Improved sort ing of GRUB2 boot menu
An issue with the sorting mechanism used by the g rub2-mkco nfi g command could cause the
grub.cfg configuration file to be generated with available kernels sorted incorrectly.
GRUB2 now uses the rpmdevtools package to sort available kernels and the configuration file is
being generated correctly with the most recent kernel version listed at the top.
Anaconda now properly revert s disk act ions when disk select ion changes
Previously, Anaconda and Blivet did not properly revert actions scheduled on disks when disk
selection changed, causing various issues. With this update, Anaconda has been fixed to create a
snapshot of the original storage configuration and return to it when disk selection changes, thus
completely reverting all actions scheduled for disks.
Improved det ect ion of device-mapper disk names
In the previous release of Red Hat Enterprise Linux 7, it was possible for the installer to crash when
installing on disks which previously contained LVM logical volumes and the metadata for those
volumes was still present. The installer could not recognize correct d evi ce-mapper names and the
process of creating new LVM logical volumes would fail.
The method used to obtain d evi ce-mapper device names has been updated and installation on
disks which contain existing LVM metadata is now more reliable.
Fixed handling of PReP Boot during part it ioning
In some circumstances, the P R eP Bo o t partition on IBM Power Systems could be set to an invalid
size during custom partitioning. In that situation, removing any partition caused the installer to
crash.
27
7 .2 Release Not es
Checks are now implemented in anaconda to ensure that the partition is always sized correctly
between 4 0 9 6 Ki B and 10 Mi B. Additionally, it is no longer necessary to change the format of the
P R eP Bo o t partition in order to change its size.
EFI part it ions on RAID1 devices
EFI System Partitions may now be created on a RAID 1 device, this is to enable system recovery when
one boot disk fails. However, because the system is only guaranteed to discover one EFI System
Partition, if the volume of the ESP that is discovered by the firmware becomes corrupt (but still
appears to be a valid ESP), and both Bo o t#### and Bo o tO rd er also become corrupt, then the
boot order will not be rebuilt automatically. In this case, the system should still boot manually from
the second disk.
T ext mode inst allat ion no longer crashes during net work configurat ion
Previously, in the Network Configuration screen in the interactive text mode installer, using a space
when specifying nameservers caused the installer to crash.
Anaconda now handles spaces in nameserver definitions in text mode correctly and the installer no
longer crashes if a space is used to separate nameserver addresses.
Rescue mode screens on IBM Syst em z are no longer cut off
Previously, the second and third screen in rescue mode on IBM System z servers were being
displayed improperly and parts of the interface were cut off. Rescue mode on this architecture has
been improved and all screens now function correctly.
OpenSCAP add-on in Anaconda
It is now possible to apply Security Content Automation Protocol (SCAP) content during the
installation process. This new installer add-on provides a reliable and easy way to configure a
security policy without having to rely on custom scripts.
This add-on provides a new Kickstart section (" % addon org_fedora_oscap" ) as well as a new screen
in the graphical user interface during an interactive installation. All three parts are documented in the
Red Hat Enterprise Linux 7 Installation Guide.
Applying a security policy during installation will perform various changes during and immediately
after the installation, depending on which policy you enable. If a profile is selected, the openscapscanner package (an OpenSCAP compliance scanning tool) is added to your package selection and
an initial compliance scan is performed after the installation finishes. Results of this scan are saved
into /ro o t/o penscap_d ata.
Several profiles are provided on installation media by the scap-security-guide package. You can also
load other content as a datastream, archive, or an RPM package from an HTTP, HTTPS or FTP
server if needed.
Note that applying a security policy is not necessary on all systems. This add-on should only be
used when a specific policy is mandated by your organization's rules or government regulations,
otherwise the add-on can be left in its default state which does not apply any security policy.
Anaconda no longer t imes out when wait ing for a Kickst art file on a CD or
DVD
28
⁠Chapt er 9 . Inst allat ion and Boot ing
Previously, if Anaconda was configured to load a Kickstart file from optical media using the
i nst. ks= cd ro m: /ks. cfg command, and the system was also booted from a CD or D VD , the
installer only waited 30 seconds for the user to swap the disk. After this time window passed, the
system entered emergency mode.
With this update, Anaconda has been modified to never time out when waiting for the user to provide
a Kickstart file on a CD or D VD . If the i nst. ks= cd ro m boot options is used and the Kickstart file is
not detected, Anaconda displays a prompt and waits until the user provides the file or reboots.
29
7 .2 Release Not es
Chapter 10. Kernel
Mult iple CPU support in kd ump on AMD64 and Int el 64 syst ems
On AMD 64 and Intel 64 systems, the kd ump kernel crash dumping mechanism can now boot with
more than one CPU enabled. This solves a problem on some systems where, due to high input and
output when creating a kernel crash dump, Linux could fail to allocate interrupts for devices when
only one CPU was enabled using the maxcpus= 1 or nr_cpus= 1 kernel options. This feature,
previously available as a Technology Preview, is now fully supported.
To enable multiple CPUs in the crash kernel, provide the nr_cpus= X option (where X is the number
of processors) on the kernel command line.
Support for kpat ch
The kp at ch utility allows users to manage a collection of binary kernel patches which can be used
to dynamically patch the kernel without rebooting. Previously, kp at ch was included as a
Technology Preview, and it is now fully supported when used under the direction of Red Hat
Customer Experience and Engagement team.
For complete details on live kernel patching support, refer to
https://access.redhat.com/solutions/2206511.
T he SHMMAX and SHMALL kernel paramet ers ret urned t o default values
Previously, the values of the kernel . shmmax and kernel . shmal l parameters, which were set in
the /usr/l i b/sysctl . d /0 0 -system. co nf file, were too low. As a consequence, some
applications, such as SAP, could not function properly. The unsuitable overrides have been
removed, and the kernel defaults, which are sufficiently high, are now used.
T ransparent huge pages no longer cause memory corrupt ion
Transparent huge pages were not being correctly synchronized during read and write operations. In
some circumstances, this resulted in memory corruption when transparent huge pages were enabled.
Memory barriers have been added to transparent huge page handling so that this memory corruption
no longer occurs.
SCSI LIO rebase
The SCSI kernel target, LIO, has been rebased from Linux-4.0.stable. This includes many bug fixes,
most critically for iSER, but also includes added support for the XCOPY, WRITE SAME, and ATS
commands; and D IF data integrity support.
makedumpfile now support s t he new sadump format represent ing up t o 16
T B of physical memory
The makedumpfile command now supports the new sadump format that can represent more than 16
TB of physical memory space. This allows users of makedumpfile to read dump files over 16 TB,
generated by sadump on certain upcoming server models.
Removing or upgrading kernel no longer displays a warning
30
⁠Chapt er 1 0 . Kernel
The weak-modules script, which is used by kmo d to manage kABI-compatible module symbolic links,
was previously removing the /l i b/mo d ul es/<versi o n>/weak-upd ates directory when
removing files associated with a kernel. This directory is owned by the kernel package and removing
it caused inconsistency between the file system and the state expected by rpm. This caused a
warning to be displayed every time a kernel was upgraded or removed.
The script has been updated to remove the contents of the weak-upd ates directory but leave the
directory itself, and warnings are no longer being displayed.
New package: libevdev
Libevdev is a low-level library for the Linux kernel input event device interface. It provides safe
interfaces to query device capabilities and process events from devices. Current versions of xorgx11-drv-evdev and xorg-x11-drv-synaptics require this library as a dependency.
T uned can now run in no-daemon mode
Previously, Tuned could run only as a daemon, which could affect performance of small systems
because of the memory footprint of the Tuned daemon. With this update, a no-daemon (one shot)
mode, which does not require any resident memory, has been added into Tuned. The no-daemon
mode is disabled by default because much of Tuned functionality is missing in this mode.
New package: t uned-profiles-realt ime
The tuned-profiles-realtime package has been added to Red Hat Enterprise Linux Server and Red Hat
Enterprise Linux for Real Time. It contains a realtime profile used by the tuned utility to perform CPU
isolation and IRQ tuning. When the profile is activated, it reads its variable section, which specifies
the CPUs to be isolated, and moves all threads that may be moved off those CPU cores.
SCSI error messages can now be int erpret ed comfort ably
Previous kernel changes to the printk() function had resulted in Small Computer System Interface
(SCSI) error messages being logged across multiple lines. As a consequence, if multiple errors
occurred across different devices, it could become difficult to interpret the error messages correctly.
This update changes the SCSI error logging code to log error messages using the dev_printk()
option, which associates each error message with the device that generated the error.
libAT A subsyst em and drivers updat ed
This enhancement update provides number of bug fixes and enhancements of the libATA subsystem
and drivers.
FCoE and DCB have been upgraded
Fibre Channel over Ethernet (FCoE) and D ata Center Bridging (D CB) kernel components have been
upgraded to the latest upstream versions, which provides a number of bug fixes and enhancements
over the previous versions.
perf rebase t o version 4 .1
31
7 .2 Release Not es
The perf packages have been upgraded to upstream version 4.1, which provides a number of
performance and stability fixes and enhancements over the previous version. Notably, this rebase
adds the Intel Cache QoS Monitoring and AMD IBS Ops features and provides support for Intel Xeon
v4 for compressed kernel modules, for parametrized events and support to specify breakpoint length.
In addition, a number of options have been added to the perf tool, such as the --system-wi d e,
to p -z, to p -w, trace --fi l ter-pi d s, and trace --event options.
Support for T PM 2.0
This update adds driver-level support for version 2.0 compliant Trusted Platform Module (TPM)
devices.
turbo stat now provides correct out put
Previously, the turbo stat tool detected if system had the MSR device support by reading the
/dev/cpu/0/msr file for cpu0 instead of cpu. As a consequence, disabling a CPU caused the CPUs to
be deleted from turbostat output. This bug has been fixed, and running the turbo stat l s command
now returns correct output.
turbo stat now support s Int el Xeon v5 processors
This enhancement adds Intel Xeon v5 processor support to the turbo stat tool.
t he zswap t ool makes use of t he zpo o l API
Previously, the zswap tool directly used zbud , a storage pool that stores compressed pages at a
ratio of 2:1 (when full). This update introduces the zpo o l API that provides access to either the zbud
or zsmal l o c pools: zsmal l o c stores compressed pages at a potential higher density, resulting in
more reclaimed memory for highly compressible pages. Within this update, zsmal l o c has been
promoted to the /mm drivers so that zpo o l works as intended.
T he /proc/pid/cmdline file lengt h is now unlimit ed
The /proc/pid/cmdline file length limit for the ps command was previously hard-coded in the kernel to
4096 characters. This update makes sure the length of /proc/pid/cmdline is unlimited, which is
especially useful for listing processes with long command line arguments.
Support for dma_rmb and dma_wmb now provided
This update introduces two new primitives for synchronizing cache coherent memory writes and
reads, dma_wmb() and dma_rmb(). This feature will be available for appropriate use in drivers.
qib HCA driver connect ion
D ue to a mismatch in SRP LOGIN ID , the SRP target previously failed to connect over the qib HCA
device driver. This update fixes the bug, and the aforementioned connection can now be established
successfully.
Increase in memory limit
Starting with Red Hat Enterprise Linux 7.2, maximum supported memory limit on AMD 64 and Intel 64
systems has been increased from 6 TB to 12 TB.
32
⁠Chapt er 1 0 . Kernel
New variables for d racut
This update introduces the following variables for the d racut initramfs generator for use in the
kernel command line:
rd . net. d hcp. retry= cnt – If this option is set, the d racut utility will try to connect through
D HCP cnt times before failing. The default is 1.
rd . net. ti meo ut. d hcp= arg – If this option is set, the d hcl i ent command is called with the ti meo ut arg option.
rd . net. ti meo ut. i fl i nk= seconds – Wait the number of seconds until the link appears. The
default is 60 seconds.
rd . net. ti meo ut. i fup= seconds – Wait the number of seconds until link has the UP state. The
default is 20 seconds.
rd . net. ti meo ut. ro ute= seconds – Wait the number of seconds until the route shows up. The
default is 20 seconds.
rd . net. ti meo ut. i pv6 d ad = seconds – Wait the number of seconds until IPv6 D AD is finished.
The default is 50 seconds.
rd . net. ti meo ut. i pv6 auto = seconds – Wait the number of seconds until IPv6 automatic
addresses are assigned. The default is 40 seconds.
rd . net. ti meo ut. carri er= seconds – Wait the number of seconds until the carrier is
recognized. The default is 5 seconds.
33
7 .2 Release Not es
Chapter 11. Networking
i4 0 e and i4 0 e vf no w fully suppo rt e d
The i40e and i40evf kernel drivers have been updated to versions 1.3.21-k and 1.3.13. These
updated drivers, which were previously included as a Technology Preview, are now fully supported.
Note that you need to apply the i40e D river Update Program (D UP) for Red Hat Enterprise Linux 7.2
available at https://rhn.redhat.com/errata/RHEA-2016-0464.html. For more information, see the
Knowledgebase article available at https://access.redhat.com/articles/1400943.
On i40e ports, an attempt to run iSCSI related commands previously led to loss of network
connectivity out of i40e ports. This update fixes the bug, and the system now allows for iSCSI
commands to proceed.
SNMP now correct ly obeys t he client addr direct ive over IPv6
Previously, the cl i entad d r option in snmp. co nf only affected outgoing messages sent over IPv4.
With this release, the outgoing IPv6 messages are correctly sent from the interface specified by
cl i entad d r.
tcpd ump support s -J, -j, and --t ime-st amp-precision opt ions
As kernel , g l i bc, and l i bpcap now provide APIs to obtain nanosecond resolutions time stamps,
tcpd ump has been updated to leverage this functionality. Users can now query which time stamp
sources are available (-J), set a specific time stamp source (-j), and request time stamps with a
specified resolution (--time-stamp-precision).
T CP/IP rebase t o version 3.18
TCP/IP stack has been upgraded to upstream version 3.18, which provides a number of bug fixes
and enhancements over the previous version. Notably, this update fixes TCP fast open extension,
which now works as expected when using IPv6. In addition, this update provides support for
optional TCP autocorking and implements D ata Center TCP (D CTCP).
Net workManager libreswan rebase t o version 1.0.6
A number of bug fixes and enhancements have been incorporated from upstream, for example:
* Password handling is now more robust
* Connection start and stop is now more robust
* D efault routing is now autodetected from pushed routes
* Added support for interactive password requests
* Fixed erroneous import and export capability advertisement.
Net workManager now support s set t ing t he MT U of a bonded int erface
Both 'nmcli' and the GUI interface now allow the setting of MTU on a bonded interface.
Net workManager now validat es IPv6 Rout er Advert isement MT U opt ions
before applying t hem
34
⁠Chapt er 1 1 . Net working
Malicious or misconfigured nodes could send an IPv6 MTU that would make further network
communication problematic or impossible if applied. NetworkManager now gracefully handles these
events and maintains IPv6 connectivity.
IPv6 Privacy ext ensions now enabled by default
To determine and set IPv6 privacy settings at device activation, NetworkManager now checks its
network configuration in NetworkManager.conf by default, and falls back to
/pro c/sys/net/i pv6 /co nf/d efaul t/use_tempad d r if necessary.
T he cont rol-cent er Net work Panel now displays WiFi device capabilit ies
Supported operating frequencies of WiFi devices are now displayed in the control-center network
panel.
Net workManager now gracefully handles rout e conflict s when mult iple
int erfaces point t o t he same gat eway
NetworkManager now keeps track of configured routes and avoids attempts to set conflicting routes.
When a conflicting route is no longer active, it is removed.
Fix for net work blackout wit h mult ihomed connect ions
NetworkManager now avoids a network blackout when activating the second device in a multihomed
connection.
New opt ion t o prevent Net workManager from overriding i p ro ute ad d
The new 'never-default' option has been added to the connection IP configuration. This option
prevents NetworkManager from setting the default route itself, allowing the administrator to set
different default routes as required.
Fix for legacy net work.service errors when Carrier Down is det ect ed on some
hardware
When a device has no carrier during boot, NetworkManager will wait for the carrier to be detected
instead of causing activation to fail immediately.
Net workManager now support s Wake On Lan
The nmcli utility now allows Wake o n Lan to be set on a per device basis.
Improved support for firewalld z ones wit h VPN connect ions
When a firewall zone is configured for a device-based VPN connection, the zone is now correctly
configured in firewalld.
Fair Queue packet scheduler now support ed
The Fair Queue packet scheduler, known as fq , has been added to Red Hat Enterprise Linux 7.2 and
can be selected using the tc (traffic controller) utility.
35
7 .2 Release Not es
Added support for t ransmit coalescing
The xmi t_mo re extension has been implemented, improving transmit performance of virtio-net and
other drivers, especially when TSO (TCP Segmentation Offload) is disabled.
Improved net work frame receiving performance
By refactoring the code to eliminate IRQ save and restore operations in NAPI memory allocation,
latency when receiving network frames has been reduced.
Significant ly improved performance of rout e lookups
The IPv4 FIB (Forward Information Base) code has been updated from upstream to improve
performance.
Net work Namespace support for Virt ual Int erfaces
The netns id is now supported on virtual interfaces, allowing reliable tracking of linked network
interfaces across network namespace boundaries.
Docker and LXC cont ainers can now read net .ipv4 .ip_local_port _range
Network name space support for the net.ipv4.ip_local_port_range sysctl has been added, improving
container support for software that requires access to this information.
Improved report ing of aut oconfigured IPv6 rout es by t he 'ip' t ool
The i p tool could not get the mtu or hoplimit information from a Route Advertisement, this has been
fixed.
Dual-st ack socket opt ions are now correct ly export ed
AF_INET6 sockets are only exclusive to IPv6 when IPV6_V6ONLY is set. In all other cases the socket
is also IPv4 capable. This information is now properly exported and can be interrogated using
iproute2.
Dat a Cent er T CP Now Support ed
This release includes an implementation of D CTCP to improve network performance in D ata Center
environments. the parameter d ctcp can be set either in sysctl or on a per route basis with i p
ro ute.
Per Rout e Congest ion Cont rol
To enable different congestion control algorithms on a per route basis, the co ng ctl parameter has
been added to i p ro ute.
Improved Congest ion Window handling for T CP Cubic and Reno when using
GRO
The method to determine bandwidth and congestion window sizing has been improved, reducing the
number of ACK packets required for transmission of large volumes of data.
36
⁠Chapt er 1 1 . Net working
T CP Pacing is now support ed
The parameter SO _MAX_P AC ING _R AT E has been added. This enables greater control of throughput
rate for environment where this is a consideration.
Support for bot h client and server T FO
The TCP Fast Open feature has been added, using the RFC 7413 assigned option number.
Mit igat ion of T CP ACK loops
Handling of duplicated TCP ACKs has been improved, preventing some problems with buggy or
potentially malicious middleboxes.
Minimal support for secondary endpoint s wit h nf_connt rack_prot o_sct p
Basic multihoming support has been added to SCTP.
AF_UNIX implement at ion rebased
The AF_UNIX (sometimes called AF_LOCAL) code has been updated to include many fixes and
enhancements. In particular, sendpage and splice (also known as zerocopy) are now supported.
Kernel t unneling support rebased t o upst ream
The kernel tunneling drivers have been updated from kernel 4, bringing in many fixes and
enhancements, especially for VXLAN.
Added support for crossing net work namespaces t o GRE
Both gre and ip6gre now have support for x-netns.
Improved performance when running Virt ual Machine T raffic over VXLAN
The transmit flow hashing code has been updated, resulting in improved performance when traffic
originating from a virtual machine is directed into a tunnel.
Improved offloading for VLAN frames received in a VXLAN or from GRE
t unnels
A number of changes have been introduced to enable GRO support and improve performance under
VXLAN and NVGRE tunneling.
Improved performance of Open vSwit ch t unneling
The tx-no cache-co py device feature is now disabled by default. The previous default created a
significant overhead for many workloads and particularly for OVS tunnels running over a VXLAN.
Improved IPsec Handling
IPsec has been updated to provide many fixes and some enhancements. Of particular note is that
this release now provides the ability to match on outgoing interfaces.
37
7 .2 Release Not es
Inclusion of VT I6 support including net ns capabilit ies
Virtual Tunnel Interfaces for IPv6, including netns capabilities, have been added to the kernel.
Default value of nf_connt rack_bucket s increased
If not specified as parameter during module loading, the default number of buckets is calculated
through dividing total memory by 16384 to determine the number of buckets. The hash table will
never have fewer than 32 and is limited to 16384 buckets. For systems with more than 4GB of memory
however, this limit will be 65536 buckets.
Improvement s in memory usage for ipt ables on large SMP machines
Previously, large iptables rulesets could use significant amounts of memory unnecessarily, this was
due to storing the ruleset on a per (possible) CPU basis. The memory overhead has been reduced by
changing the way rulesets are stored.
Net work bonding driver updat ed
To improve maintainability, the kernel network bonding driver has been updated to bring it in line
with upstream source.
Kernel net link int erfaces for bonding and 802.3ad (LACP)
Additional netlink interfaces for reading and setting bonding parameters on LACP devices have been
added to the kernel.
Improvement s in performance for mact ap and macvt ap wit h VLANs
Several low throughput issues involving segmentation problems have been addressed:
* Communicating with e1000 devices to virtio devices over mactap.
* Communicating with an external host when using VLANs in the guest.
* Communicating with the KVM host over a VLAN in both the guest and host.
Improved et ht ool net work querying
The network-querying capabilities of the ethtool utility were enhanced in a Technology Preview for
Red Hat Enterprise Linux 7.1 on IBM System z and are fully supported as of Red Hat Enterprise Linux
7.2. As a result, when using hardware compatible with the improved querying, ethtool provides
improved monitoring options, and displays network card settings and values more accurately.
38
⁠Chapt er 1 2 . Securit y
Chapter 12. Security
GSSAPI key-exchange algorit hms can now be select ively disabled
In view of the Logjam security vulnerability, the g ss-g ro up1-sha1-* key-exchange methods are no
longer considered secure. While there was the possibility to disable this key-exchange method as a
normal key exchange, it was not possible to disable it as a GSSAPI key exchange. With this update,
the administrator can selectively disable this or other algorithms used by the GSSAPI key exchange.
SELinux policy for Red Hat Glust er St orage has been added
Previously, SELinux policy for Red Hat Gluster Storage (RHGS) components was missing, and
Gluster worked correctly only when SELinux was in permissive mode. With this update, SELinux
policy rules for the g l usterd (glusterFS Management Service), g l usterfsd (NFS sever), smbd ,
nfsd , rpcd , adn ctd bd processes have been updated providing SELinux support for Gluster.
openscap rebase t o version 1.2.5
The openscap packages have been upgraded to upstream version 1.2.5, which provides a number of
bug fixes and enhancements over the previous version.
Notable enhancements include:
* Support for OVAL version 5.11, which brings multiple improvements such as for systemd properties
* Introduced native support of xml . bz2 input files
* Introduced the o scap-ssh tool for assessing remote systems
* Introduced the o scap-d o cker tool for assessing containers/images
scap-securit y-guide rebase t o version 0.1.25
The scap-security-guide tool has been upgraded to upstream version 0.1.25, which provides a
number of bug fixes and enhancements over the previous version.
Notable enhancements include:
* New security profiles for Red Hat Enterprise Linux 7 Server: Common Profile for General-Purpose
Systems, D raft PCI-D SS v3 Control Baseline, Standard System Security Profile, and D raft STIG for
Red Hat Enterprise Linux 7 Server.
* New security benchmarks for Firefox and Java Runtime Environment (JRE) components running on
Red Hat Enterprise Linux 6 and 7.
* New scap-securi ty-g ui d e-d o c subpackage, which contains HTML-formatted documents
containing security guides generated from XCCD F benchmarks (for every security profile shipped in
security benchmarks for Red Hat Enterprise Linux 6 and 7, Firefox, and JRE).
39
7 .2 Release Not es
Chapter 13. Servers and Services
T he ErrorPolicy direct ive is now validat ed
The ErrorPolicy configuration directive was not validated on startup, and an unintended default error
policy could be used without a warning. The directive is now validated on startup and reset to the
default if the configured value is incorrect. The intended policy is used, or a warning message is
logged.
CUPS now disables SSLv3 encrypt ion by default
Previously, it was not possible to disable SSLv3 encryption in the CUPS scheduler, which left it
vulnerable to attacks against SSLv3. To solve this issue, the cupsd . co nf SSLO pti o ns keyword
has been extended to include two new options, Al l o wR C 4 and Al l o wSSL3, each of which enables
the named feature in cupsd . The new options are also supported in the /etc/cups/cl i ent. co nf
file. The default is now to disable both RC4 and SSL3 for cupsd .
cups now allows underscore in print er names
The cups service now allows users to include the underscore character (_) in local printer names.
Unneeded dependency removed from t he t ft p-server package
Previously, an additional package was installed by default when installing the tftp-server package.
With this update, the superfluous package dependency has been removed, and the unneeded
package is no longer installed by default when installing tftp-server.
T he deprecat ed /et c/sysconfig/conman file has been removed
Before introducing the systemd manager, various limits for services could be configured in the
/etc/sysco nfi g /co nman file. After migrating to systemd , /etc/sysco nfi g /co nman is no
longer used and therefore it was removed. To set limits and other daemon parameters, such as
LimitCPU=, LimitD ATA=, or LimitCORE=, edit the co nman. servi ce file. For more information, see the
systemd.exec(5) manual page. In addition, a new variable LimitNOFILE=10000 has been added to
the systemd . servi ce file. This variable is commented out by default. Note that after making any
changes to the systemd configuration, the systemctl d aemo n-rel o ad command must be
executed for changes to take effect.
mod_nss rebase t o version 1.0.11
The mod_nss packages have been upgraded to upstream version 1.0.11, which provides a number of
bug fixes and enhancements over the previous version. Notably, mo d _nss can now enable TLSv1.2,
and SSLv2 has been completely removed. Also, support for the ciphers generally considered to be
most secure has been added.
T he vsft pd daemon now support s DHE and ECDHE cipher suit es
The vsftpd daemon now supports cipher suites based on the D iffie–Hellman Exchange (D HE) and
Elliptic Curve D iffie–Hellman Exchange (ECD HE) key-exchange protocol.
Permissions can now be set for files uploaded wit h sft p
40
⁠Chapt er 1 3. Servers and Services
Inconsistent user environments and strict umask settings could result in inaccessible files when
uploading using the sftp utility. With this update, the administrator is able to force exact
permissions for files uploaded using sftp, thus avoiding the described issue.
LDAP queries used by ssh-ldap-helper can now be adjust ed
Not all LD AP servers use a default schema as expected by the ssh-l d ap-hel per tool. This update
makes it possible for the administrator to adjust the LD AP query used by ssh-l d ap-hel per to get
public keys from servers using a different schema. D efault functionality stays untouched.
A new createo l d d i r direct ive in t he logrot at e ut ilit y
A new logrotate createo l d d i r directive has been added to enable automatic creation of the
o l d d i r directory. For more information, see the logrotate(8) manual page.
Error messages from /etc/cro n. d ai l y/l o g ro tate are no longer redirect ed t o
/d ev/nul l
Error messages generated by the daily cronjob of l o g ro tate are now sent to the ro o t user instead
of being silently discarded. In addition, the /etc/cro n. d ai l y/l o g ro tate script is marked as a
configuration file in RPM.
SEED and IDEA based algorit hms rest rict ed in mo d _ssl
The set of cipher suites enabled by default in the mo d _ssl module of the Apache HTTP Server has
been restricted to improve security. SEED and ID EA based encryption algorithms are no longer
enabled in the default configuration of mo d _ssl .
Apache HT T P Server now support s UPN
Names stored in the subject al ternati ve name portion of SSL/TLS client certificates, such as
the Microsoft User Principle Name, can now be used from the SSLUserName directive and are now
available in mo d _ssl environment variables. Users can now authenticate with their Common Access
Card (CAC) or certificate with a UPN in it, and have their UPN used as authenticated user information,
consumed by both the access control in Apache and using the R EMO T E_USER environment variable
or a similar mechanism in applications. As a result, users can now set SSLUserName
SSL_C LIENT _SAN_O T HER _msUP N_0 for authentication using UPN.
T he mo d _d av lock dat abase is now enabled by default in t he mo d _d av_fs
module
The mo d _d av lock database is now enabled by default if the Apache HTTP mo d _d av_fs module is
loaded. The default location ServerR o o t/d avl o ckd b can be overridden using the D AVLo ckD B
configuration directive.
mo d _pro xy_wstunnel now support s WebSocket s
The Apache HTTP mo d _pro xy_wstunnel module is now enabled by default and it includes
support for SSL connections in the wss: // scheme. Additionally, it is possible to use the ws: //
scheme in the mo d _rewri te directives. This allows for using WebSockets as a target to
mo d _rewri te and enabling WebSockets in the proxy module.
41
7 .2 Release Not es
A T uned profile opt imiz ed for Oracle dat abase servers has been included
A new o racl e T u n ed profile, which is specifically optimized for the Oracle databases load, is now
available. The new profile is delivered in the tuned-profiles-oracle subpackage, so that other related
profiles can be added in the future. The o racl e profile is based on the enterpri se-sto rag e
profile, but modifies kernel parameters based on Oracle database requirements and turns
transparent huge pages off.
42
⁠Chapt er 1 4 . St orage
Chapter 14. Storage
DM rebase t o version 4 .2
D evice Mapper (D M) has been upgraded to upstream version 4.2, which provides a number of bug
fixes and enhancements over the previous version including a significant D M crypt performance
update and D M core update to support Multi-Queue Block I/O Queueing Mechanism (blk-mq).
Mult iqueue I/O scheduling wit h blk-mq
Red Hat Enterprise Linux 7.2 includes a new multiple queue I/O scheduling mechanism for block
devices known as blk-mq. It can improve performance by allowing certain device drivers to map I/O
requests to multiple hardware or software queues. The improved performance comes from reducing
lock contention present when multiple threads of execution perform I/O to a single device. Newer
devices, such as Non-Volatile Memory Express (NVMe), are best positioned to take advantage of this
feature due to their native support for multiple hardware submission and completion queues, and
their low-latency performance characteristics. Performance gains, as always, will depend on the
exact hardware and workload.
The blk-mq feature is currently implemented, and enabled by default, in the following drivers: virtioblk, mtip32xx, nvme, and rbd.
The related feature, scsi-mq, allows Small Computer System Interface (SCSI) device drivers to use the
blk-mq infrastructure. The scsi-mq feature is provided as a Technology Preview in Red Hat Enterprise
Linux 7.2. To enable scsi-mq, specify scsi _mo d . use_bl k_mq = y on the kernel command line. The
default value is n (disabled).
The device mapper (D M) multipath target, which uses request-based D M, can also be configured to
use the blk-mq infrastructure if the d m_mo d . use_bl k_mq = y kernel option is specified. The default
value is n (disabled).
It may be beneficial to set d m_mo d . use_bl k_mq = y if the underlying SCSI devices are also using
blk-mq, as doing so reduces locking overhead at the D M layer.
To determine whether D M multipath is using blk-mq on a system, cat the file /sys/bl o ck/d mX/d m/use_bl k_mq , where d m-X is replaced by the D M multipath device of interest. This file is readonly and reflects what the global value in /sys/mo d ul e/d m_mo d /parameters/use_bl k_mq was
at the time the request-based D M multipath device was created.
New delay_wat ch_checks and delay_wait _checks opt ions in t he mult ipat h.conf
file
Should a path be unreliable, as when the connection drops in and out frequently, multipathd will still
continuously attempt to use that path. The timeout before multipathd realizes that the path is no
longer accessible is 300 seconds, which can give the appearance that multipathd has stalled.
To fix this, two new configuration options have been added: delay_watch_checks and
delay_wait_checks. Set the delay_watch_checks to how many cycles multipathd is to watch the path
for after it comes online. Should the path fail in under that assigned value, multipathd will not use it.
multipathd will then rely on the delay_wait_checks option to tell it how many consecutive cycles it
must pass until the path becomes valid again. This prevents unreliable paths from immediately being
used as soon as they come back online.
New config_dir opt ion in t he mult ipat h.conf file
43
7 .2 Release Not es
Users were unable to split their configuration between /etc/multipath.conf and other configuration
files. This prevented users from setting up one main configuration file for all their machines and keep
machine-specific configuration information in separate configuration files for each machine.
To address this, a new config_dir option was added in the multipath.config file. Users must change
the config_dir option to either an empty string or a fully qualified directory path name. When set to
anything other than an empty string, multipath will read all .conf files in alphabetical order. It will then
apply the configurations exactly as if they had been added to the /etc/multipath.conf. If this change is
not made, config_dir defaults to /etc/multipath/conf.d.
New dmst at s command t o display and manage I/O st at ist ics for regions of
devices t hat use t he device-mapper driver
The d mstats command provides userspace support for device-mapper I/O statistics. This allows a
user to create, manage and report I/O counters, metrics and latency histogram data for user-defined
arbitrary regions of device-mapper devices. Statistics fields are now available in d msetup reports
and the d mstats command adds new specialized reporting modes designed for use with statistics
information. For information on the d mstats command, see the dmstats(8) man page.
⁠LVM Cache
LVM cache has been fully supported since Red Hat Enterprise Linux 7.1. This feature allows users to
create logical volumes (LVs) with a small fast device performing as a cache to larger slower devices.
Refer to the lvmcache(7) manual page for information on creating cache logical volumes.
Note the following restrictions on the use of cache LVs:
* The cache LV must be a top-level device. It cannot be used as a thin-pool LV, an image of a RAID
LV, or any other sub-LV type.
* The cache LV sub-LVs (the origin LV, metadata LV, and data LV) can only be of linear, stripe, or
RAID type.
* The properties of the cache LV cannot be changed after creation. To change cache properties,
remove the cache as described in lvmcache(7) and recreate it with the desired properties.
New LVM/DM cache policy
A new smq dm-cache policy has been written that the reduces memory consumption and improves
performance for most use cases. It is now the default cache policy for new LVM cache logical
volumes. Users who prefer to use the legacy mq cache policy can still do so by supplying the —
cachepo l i cy argument when creating the cache logical volume.
LVM syst emID
LVM volume groups can now be assigned an owner. The volume group owner is the system ID of a
host. Only the host with the given system ID can use the VG. This can benefit volume groups that
exist on shared devices, visible to multiple hosts, which are otherwise not protected from concurrent
use from multiple hosts. LVM volume groups on shared devices with an assigned system ID are
owned by one host and protected from other hosts.
New l vmpo l l d daemon
44
⁠Chapt er 1 4 . St orage
The l vmpo l l d daemon provides a polling method for long-running LVM commands. When
enabled, control of long-running LVM commands is transferred from the original LVM command to the
l vmpo l l d daemon. This allows the operation to continue independent of the original LVM
command. The l vmpo l l d daemon is enabled by default.
Before the introduction of the l vmpo l l d daemon, any background polling process originating in
an lvm2 command initiated inside a cg ro up of a systemd service could get killed if the main process
(the main service) exited in the cg ro up. This could lead to premature termination of the lvm2 polling
process. Additionally, l vmpo l l d helps to prevent spawning lvm2 polling processes querying for
progress on the same task multiple times because it tracks the progress for all polling tasks in
progress.
For further information on the l vmpo l l d daemon, see the l vm. co nf configuration file.
Enhancement s t o LVM select ion crit eria
The Red Hat Enterprise Linux 7.2 release supports several enhancements to LVM selection criteria.
Previously, it was possible to use selection criteria only for reporting commands; LVM now supports
selection criteria for several LVM processing commands as well. Additionally, there are several
changes in this release to provide better support for time reporting fields and selection.
For information on the implementation of these new features, see the LVM Sel ecti o n C ri teri a
appendix in the Logical Volume Administration manual.
T he default maximum number of SCSI LUNs is increased
The default value for the max_repo rt_l uns parameter has been increased from 511 to 16393. This
parameter specifies the maximum number of logical units that may be configured when the systems
scans the SCSI interconnect using the Report LUNs mechanism.
45
7 .2 Release Not es
Chapter 15. System and Subscription Management
PowerT OP now respect s user-defined report file names
Previously, PowerTOP report file names were generated in an unclear, undocumented way. With this
update, the implementation has been improved, and the generated file names now respect the names
requested by the user. This applies to both CSV and HTML reports.
Amended yum-co nfi g -manag er commands
Previously, running the yum-co nfi g -manag er --d i sabl e command disabled all configured
repositories, while the yum-co nfi g -manag er --enabl e command did not enable any. This
inconsistency has been fixed. The --d i sabl e and --enabl e commands now require the use of '\*'
in the syntax, and yum-co nfi g -manag er --enabl e \* enables repositories. Running the
commands without the addition of '\*' prints a message asking the user to run yum-co nfi g manag er --d i sabl e \* or yum-co nfi g -manag er --enabl e \* if they want to disable or
enable repositories.
New search-disabled-repos plug-in for yum
The search-disabled-repos plug-in for yum has been added to the subscription-manager packages.
This plug-in allows users to successfully complete yum operations that fail due to the source
repository being dependent on a disabled repository. When search-disabled-repos is installed in the
described scenario, yum displays instructions to temporarily enable repositories that are currently
disabled and to search for missing dependencies.
If you choose to follow the instructions and turn off the default notify_only behavior in the
/etc/yum/pluginconf.d/search-disabled-repos.conf file, future yum operations will prompt you to
temporarily or permanently enable all the disabled repositories needed to fulfill the yum transaction.
Acquiring hypervisor dat a in parallel
With this update, virt-who is able to acquire data from multiple hypervisors in parallel. Previously,
virt-who could read data only from a single hypervisor at a time, and if one hypervisor in a series was
nonfunctional, virt-who waited for its response and thus failed. Reading parallel hypervisors works
around this problem and prevents the described failure.
Filt ering for hypervisors report ed by virt -who
The virt-who service introduces a filtering mechanism for the Subscription Manager reports. As a
result, users can now choose which hosts virt-who should display according to the specified
parameters. For example, they can filter out hosts that do not run any Red Hat Enterprise Linux
guests, or hosts that run guests of a specified version of Red Hat Enterprise Linux.
Improved visualiz at ion of host -t o-guest associat ion
The -p option has been added to the virt-who utility. When used with -p, virt-who output displays
Javascript Object Notation (JSON)-encoded map of the host-guest association. In addition, the
information on host-guest association logged in the /var/log/rhsm/rhsm.log file is now formatted in
JSON as well.
virt -who out put displayed as host names
46
⁠Chapt er 1 5. Syst em and Subscript ion Management
It is now possible to configure the virt-who query so that its results are displayed as host names
instead of as Universally Unique Identifiers (UUID s) when viewed in Red Hat Satellite and Red Hat
Customer Portal. To enable the function, add the hypervi so r_i d = ho stname option to the
configuration file in the /etc/virt-who.d/ directory. Ideally, this should be done before using virt-who
for the first time, otherwise changing the configuration duplicates the hypervisor.
Pre-filled virt -who configurat ion file
A default configuration file for virt-who has been placed in the /etc/virt-who.d/ directory. It contains a
template and instructions for the user to configure virt-who. This replaces the deprecated
configuration that uses the /etc/sysconfig/virt-who file.
Enhanced proxy connect ion opt ions
With Red Hat Enterprise Linux 7.2, the virt-who utility can handle the HTTP_PROXY and
HTTPS_PROXY environment variables, and thus correctly uses the proxy server when requested.
This allows virt-who to connect to the Hyper-V hypervisor and Red Hat Enterprise Virtualization
Manager through proxy.
Subscript ion Manager now support s syslog
The subscription-manager tool can now use the syslog as the log handler and formatter in addition to
separate log used previously. The handler and formatter is configured in the
/etc/rhsm/l o g g i ng . co nf configuration file.
Subscript ion Manager is now part of Init ial Set up
The Subscription Manager component of Firstboot has been ported to the Initial Setup utility. Users
are now able to register the system from the main menu of Initial Setup after installing a Red Hat
Enterprise Linux 7 system and rebooting for the first time.
Subscript ion Manager now displays t he server URL when regist ering on a
command line
When registering a system using the subscri pti o n-manag er command on a command line, the
tool now also shows the URL of the server being used for the registration when asking for user name
and password. This helps the user determine which credentials to use.
Manage Reposit ories dialog in Subscript ion Manager is now more responsive
The Manage Repositories dialog in the graphical version of Subscription Manager (the subscriptionmanager-gui package) has been updated to no longer fetch information on each checkbox change.
Instead, the system state is only synchronized when the new save button is clicked. This removes
delays users experienced in previous versions caused by the system state being updated on each
checkbox action, and repository management is now significantly more responsive.
ReaR now works also on int erfaces ot her t han et h0
Previously, the rescue system produced by ReaR did not support mounting an NFS server using an
interface other than eth0. In that case, the rescue system and backup files could not be downloaded
and the system could not be restored. With this update, this has been fixed, and other interfaces,
such as eth1, eth2, and so on, can now be used.
47
7 .2 Release Not es
Chapter 16. Virtualization
qemu-kvm support s virt ual machine shut down t race event s
Support has been added for qemu-kvm trace events during the virtual machine system shutdown
process, which allows users to get detailed diagnostics about a guest system's shutdown requests
issued by the vi rsh shutd o wn command or by the virt-manager application. This provides users
with enhanced capabilities for isolating and debugging KVM guest problems during shutdown.
Int el MPX exposed t o t he guest
With this update, qemu-kvm allows the Intel Memory Protection Extensions (MPX) feature to be
exposed to the guest. On the Intel 64 host systems that support MPX, this enables the use of a set of
extensions that provide hardware support for bounds protection on pointer references.
Guest memory dump ext ract ion from t he qemu-kvm core
The dump-guest-memory.py script has been introduced into QEMU, which makes it possible to
analyze a guest memory dump from the qemu-kvm core in case of a guest kernel failure. For further
information, see the related help text by using the hel p d ump-g uest-memo ry command.
virt -v2v is fully support ed
With Red Hat Enterprise Linux 7.2, the virt-v2v command-line tool has become fully supported. This
tool converts virtual machines running on foreign hypervisors to run on KVM. Currently, virt-v2v can
convert Red Hat Enterprise Linux and Windows guests running on Red Hat Enterprise Linux 5 Xen
and VMware vCenter.
Virt ualiz at ion on IBM Power Syst ems
Red Hat Enterprise Linux with KVM is supported on AMD 64 and Intel 64 systems, but not on IBM
Power Systems. Red Hat currently provides a POWER8-based solution with Red Hat Enterprise
Virtualization for IBM Power Systems.
More information on version support and installation procedures can be found in the following
Knowledge Base article: https://access.redhat.com/articles/1247773.
Hyper-V T RIM support
Now it is possible to use Thin Provisioned Hyper-V virtual hard disk (VHD X). The update adds
support to shrink the underlining VHD X files for Microsoft Hyper-V virtual machines to actual used
size.
KVM support for t cmalloc
KVM can now use the tcmalloc library, which provides a significant performance improvement in I/O
operations per second.
Select ive disk copying during domain live migrat ion
When live migrating a domain as well as its disks, the user can now select which disks are copied
during the migration. This allows for more efficient live migration when copying certain disks is
undesirable, such as when they already exist on the destination, or when they are no longer useful.
48
⁠Chapt er 1 6 . Virt ualiz at ion
Devices t hat use RMRRs are now excluded from IOMMU API domains
Under the changes made to Red Hat Enterprise Linux 7.1, when an attempt is made to assign a device
that is entangled by an Reserved Memory Region Reporting (RMRR) association, the kernel reports
the following error in the dmesg log:
" D evice is ineligible for IOMMU domain attach due to platform RMRR requirement. Contact your
platform vendor."
The platform vendor has the ability to request that the VT-d IOMMU subsystem within the kernel retain
specific mappings for devices using entries in the Advanced Configuration and Power Interface
D irect Memory Access Remapping (ACPI D MAR) table known as RMRR structures. However, QEMUKVM and VFIO have no visibility to these mapping requirements and no API exists to disable any
potential ongoing communication that may occur through these regions. Therefore, a device
associated with an RMRR could continue to use D MA through this address space even after the
device was assigned to a guest VM. This could cause a device to overwrite VM memory with D MA
data intended for the memory described by the RMRR.
To fix this bug, devices with associated RMRRs are excluded from participating in the kernel internal
IOMMU API. Users can now identify such devices using dmesg logs and are also protected from
assignment of devices making use of mappings which have the ability to cause instability within
guest virtual machines. Users prevented from making use of PCI device assignment as a result of this
change should contact their platform vendor for a BIOS update to release the I/O device from the
imposed RMRR requirement.
For further information on these changes, see the following Knowledgebase article:
https://access.redhat.com/articles/1434873
New package: WALinuxAgent
The Microsoft Azure Linux Agent (WALA) version 2.0.13 has been included in the Extras channel.
This agent supports the provisioning and running of Linux Virtual Machines in the Windows Azure
cloud and should be installed on Linux images that are built to run in the Windows Azure
environment.
49
7 .2 Release Not es
Chapter 17. Atomic Host and Containers
Red Hat Ent erprise Linux At omic Host
Red Hat Enterprise Linux Atomic Host is a secure, lightweight, and minimal-footprint operating system
optimized to run Linux containers.
The Atomic Host and Containers Release Notes are now published in a separate book. For the latest
new features, known issues, and Technology Previews, see
https://access.redhat.com/documentation/en/red-hat-enterprise-linux-atomic-host/7/single/releasenotes/.
50
⁠Chapt er 1 8 . Red Hat Soft ware Collect ions
Chapter 18. Red Hat Software Collections
Red Hat Software Collections is a Red Hat content set that provides a set of dynamic programming
languages, database servers, and related packages that you can install and use on all supported
releases of Red Hat Enterprise Linux 6 and Red Hat Enterprise Linux 7 on AMD 64 and Intel 64
architectures.
D ynamic languages, database servers, and other tools distributed with Red Hat Software Collections
do not replace the default system tools provided with Red Hat Enterprise Linux, nor are they used in
preference to these tools. Red Hat Software Collections uses an alternative packaging mechanism
based on the scl utility to provide a parallel set of packages. This set allows for optional use of
alternative package versions on Red Hat Enterprise Linux. By using the scl utility, users can pick
and choose which package version they want to run at any time.
Red Hat D eveloper Toolset is now a part of Red Hat Software Collections. It is included as a separate
Software Collection. Red Hat D eveloper Toolset is designed for developers working on the Red Hat
Enterprise Linux platform. It provides current versions of the GNU Compiler Collection, GNU
D ebugger, Eclipse development platform, and other development, debugging, and performance
monitoring tools.
Important
Red Hat Software Collections has a shorter life cycle and support term than Red Hat
Enterprise Linux. For more information, see the Red Hat Software Collections Product Life
Cycle.
See the Red Hat Software Collections documentation for the components included in the set, system
requirements, known problems, usage, and specifics of individual Software Collections.
See the Red Hat D eveloper Toolset documentation for more information about the components
included in this Software Collection, installation, usage, known problems, and more.
51
7 .2 Release Not es
⁠Part II. Technology Previews
This part provides an overview of Technology Previews introduced or updated in Red Hat
Enterprise Linux 7.2.
For more information on Red Hat Technology Preview features support scope, see
https://access.redhat.com/support/offerings/techpreview/.
52
⁠Chapt er 1 9 . Aut hent icat ion and Int eroperabilit y
Chapter 19. Authentication and Interoperability
Use of AD and LDAP sudo providers
The Active D irectory (AD ) provider is a back end used to connect to an AD server. In Red Hat
Enterprise Linux 7.2, using the AD sudo provider together with the LD AP provider is supported as a
Technology Preview. To enable the AD sudo provider, add the sud o _pro vi d er= ad setting in the
[domain] section of the sssd . co nf file.
DNSSEC available as T echnology Preview in Ident it y Management
Identity Management servers with integrated D NS now support D NS Security Extensions (D NSSEC),
a set of extensions to D NS that enhance security of the D NS protocol. D NS zones hosted on Identity
Management servers can be automatically signed using D NSSEC. The cryptographic keys are
automatically generated and rotated.
Users who decide to secure their D NS zones with D NSSEC are advised to read and follow these
documents:
D NSSEC Operational Practices, Version 2: http://tools.ietf.org/html/rfc6781#section-2
Secure D omain Name System (D NS) D eployment Guide: http://dx.doi.org/10.6028/NIST.SP.800-81-2
D NSSEC Key Rollover Timing Considerations: http://tools.ietf.org/html/rfc7583
Note that Identity Management servers with integrated D NS use D NSSEC to validate D NS answers
obtained from other D NS servers. This might affect the availability of D NS zones that are not
configured in accordance with recommended naming practices described in the Red Hat Enterprise
Linux Networking Guide: https://access.redhat.com/documentation/enUS/Red_Hat_Enterprise_Linux/7/html/Networking_Guide/ch-Configure_Host_Names.html#secRecommended_Naming_Practices.
Nunc St ans event framework available for Direct ory Server
A new Nunc Stans event framework to handle multiple simultaneous connections has been added as
Technology Preview. The framework allows supporting several thousand active connections with no
performance degradation. It is disabled by default.
Browser for t he JSON-RPC API in IdM is available
This update implements a browser for the JSON-RPC API in Identity Management. The browser can
be used to view the API. Note that this feature is experimental and the API is not yet supported.
New packages: ipsilon
The ipsilon packages provide the Ipsilon identity provider service for federated single sign-on (SSO).
Ipsilon links authentication providers and applications or utilities to allow for SSO. It includes a
server and utilities to configure Apache-based service providers.
The Ipsilon server and toolkit is designed to configure Apache-based identity Service Providers. The
server is a pluggable self-contained mo d _wsg i application that provides federated SSO to web
applications.
Ipsilon is introduced in this release as a Technology Preview. Customers are advised not to consider
integration of this service for production environments at this time.
53
7 .2 Release Not es
Chapter 20. Clustering
Support for cl ufter, a t ool for t ransforming and analyz ing clust er
configurat ion format s
The clufter package, available as a Technology Preview in Red Hat Enterprise Linux 7, provides a
tool for transforming and analyzing cluster configuration formats. It can be used to assist with
migration from an older stack configuration to a newer configuration that leverages Pacemaker. For
information on the capabilities of cl ufter, see the cl ufter(1) man page or the output of the
cl ufter -h command.
54
⁠Chapt er 2 1 . File Syst ems
Chapter 21. File Systems
OverlayFS
OverlayFS is a type of union file system. It allows the user to overlay one file system on top of
another. Changes are recorded in the upper file system, while the lower file system remains
unmodified. This allows multiple users to share a file-system image, such as a container or a D VD ROM, where the base image is on read-only media. Refer to the kernel file
D ocumentation/filesystems/overlayfs.txt for additional information.
OverlayFS remains a Technology Preview in Red Hat Enterprise Linux 7.2 under most circumstances.
As such, the kernel will log warnings when this technology is activated.
Full support is available for OverlayFS when used with D ocker under the following restrictions:
* OverlayFS is only supported for use as a D ocker graph driver. Its use can only be supported for
container COW content, not for persistent storage. Any persistent storage must be placed on nonOverlayFS volumes to be supported. Only default D ocker configuration can be used; that is, one
level of overlay, one lowerdir, and both lower and upper levels are on the same file system.
* Only XFS is currently supported for use as a lower layer file system.
* SELinux must be enabled and in enforcing mode on the physical machine, but must be disabled in
the container when performing container separation; that is, /etc/sysconfig/docker must not contain -selinux-enabled. SELinux support for OverlayFS is being worked on upstream, and is expected in a
future release.
* The OverlayFS kernel ABI and userspace behavior are not considered stable, and may see
changes in future updates.
* In order to make the yum and rpm utilities work properly inside the container, the user should be
using the yum-plugin-ovl packages.
Note that OverlayFS provides a restricted set of the POSIX standards. Test your application
thoroughly before deploying it with OverlayFS.
Note that XFS file systems must be created with the -n ftype= 1 option enabled for use as an
overlay. With the rootfs and any file systems created during system installation, set the -mkfso pti o ns= -n ftype= 1 parameters in the Anaconda kickstart. When creating a new file system
after the installation, run the # mkfs -t xfs -n ftype= 1 /P AT H/T O /D EVIC E command. To
determine whether an existing file system is eligible for use as an overlay, run the # xfs_i nfo
/P AT H/T O /D EVIC E | g rep ftype command to see if the ftype= 1 option is enabled.
There are also several known issues associated with OverlayFS as of Red Hat Enterprise Linux 7.2
release. For details, see 'Non-standard behavior' in the D ocumentation/filesystems/overlayfs.txt file.
Support for NFSv4 client s wit h flexible file layout
Red Hat Enterprise Linux 7.2 adds support for flexible file layout on NFSv4 clients. This technology
enables advanced features such as non-disruptive file mobility and client-side mirroring, providing
enhanced usability in areas such as databases, big data and virtualization.
See https://datatracker.ietf.org/doc/draft-ietf-nfsv4-flex-files/ for detailed information about NFS
flexible file layout.
Bt rfs file syst em
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7 .2 Release Not es
The Btrfs (B-Tree) file system is supported as a Technology Preview in Red Hat Enterprise Linux 7.2.
This file system offers advanced management, reliability, and scalability features. It enables users to
create snapshots, it enables compression and integrated device management.
pNFS Block Layout Support
As a Technology Preview, the upstream code has been backported to the Red Hat Enterprise Linux
client to provide pNFS block layout support.
56
⁠Chapt er 2 2 . Hardware Enablement
Chapter 22. Hardware Enablement
Runt ime Inst rument at ion for IBM Syst em z
Support for the Runtime Instrumentation feature is available as a Technology Preview in Red Hat
Enterprise Linux 7.2 on IBM System z. Runtime Instrumentation enables advanced analysis and
execution for a number of user-space applications available with the IBM zEnterprise EC12 system.
LSI Syncro CS HA-DAS adapt ers
Red Hat Enterprise Linux 7.1 included code in the megaraid_sas driver to enable LSI Syncro CS
high-availability direct-attached storage (HA-D AS) adapters. While the megaraid_sas driver is fully
supported for previously enabled adapters, the use of this driver for Syncro CS is available as a
Technology Preview. Support for this adapter is provided directly by LSI, your system integrator, or
system vendor. Users deploying Syncro CS on Red Hat Enterprise Linux 7.2 are encouraged to
provide feedback to Red Hat and LSI. For more information on LSI Syncro CS solutions, please visit
http://www.lsi.com/products/shared-das/pages/default.aspx.
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7 .2 Release Not es
Chapter 23. Kernel
T he criu t ool
Red Hat Enterprise Linux 7.2 introduces the cri u tool as a Technology Preview. This tool implements
C heckpo i nt/R esto re i n User-space, which can be used to freeze a running application and
store it as a collection of files. Later, the application can be restored from its frozen state.
The cri u tool depends on P ro to co l Buffers, a language-neutral, platform-neutral extensible
mechanism for serializing structured data. The protobuf and protobuf-c packages, which provide this
dependency, are also added to Red Hat Enterprise Linux 7.2 as a Technology Preview.
User namespace
This feature provides additional security to servers running Linux containers by providing better
isolation between the host and the containers. Administrators of a container are no longer able to
perform administrative operations on the host, which increases security.
LPAR Wat chdog for IBM Syst em z
An enhanced watchdog driver for IBM System z is available as a Technology Preview. This driver
supports Linux logical partitions (LPAR) as well as Linux guests in the z/VM hypervisor, and provides
automatic reboot and automatic dump capabilities if a Linux system becomes unresponsive.
i4 0evf handles big reset s
The most common type of reset that the Virtual Function (VF) encounters is a Physical Function (PF)
reset that cascades down into a VF reset for each VF. However, for 'bigger' resets, such as a Core or
EMP reset, when the device is reinitialized, the VF previously did not get the same VSI, so the VF was
not able to recover, as it continued to request resources for its original VSI. As a Technology Preview,
this update adds an extra state to the admin queue state machine, so that the driver can re-request its
configuration information at runtime. D uring reset recovery, this bit is set in the aq_required field, and
the configuration information is fetched before attempting to bring the driver back up.
Support for Int el® Omni-Pat h Archit ect ure kernel driver
Intel® Omni-Path Architecture (OPA) kernel driver, which is supported as a Technology Preview,
provides Host Fabric Interconnect (HFI) hardware with initialization and setup for high performance
data transfers (high bandwidth, high message rate, low latency) between compute and I/O nodes in a
clustered environment.
For instructions on how to obtain Intel® Omni-Path documentation, see
https://access.redhat.com/articles/2039623.
Support for Diag0c on IBM Syst em z
As a Technology Preview, Red Hat Enterprise Linux 7.2 introduces support for the D iag0c feature on
IBM System z. D iag0c support makes it possible to read the CPU performance metrics provided by
the z/VM hypervisor, and allows obtaining the management time for each online CPU of a Linux guest
where the diagnose task is executed.
10GbE RoCE Express feat ure for RDMA
58
⁠Chapt er 2 3. Kernel
As a Technology Preview, Red Hat Enterprise Linux 7.2 includes the 10GbE RD MA over Converged
Ethernet (RoCE) Express feature. This makes it possible to use Ethernet and Remote D irect Memory
Access (RD MA), as well as the D irect Access Programming Library (D APL) and OpenFabrics
Enterprise D istribution (OFED ) APIs, on IBM System z.
Before using this feature on an IBM z13 system, ensure that the minimum required service is applied:
z/VM APAR UM34525 and HW ycode N98778.057 (bundle 14).
z EDC compression on IBM Syst em z
Red Hat Enterprise Linux 7.2 includes the Generic Workqueue (GenWQE) engine device driver as a
Technology Preview. The initial task of the driver is to perform zlib-style compression and
decompression of the RFC1950, RFC1951 and RFC1952 formats, but it can be adjusted to accelerate
a variety of other tasks.
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Chapter 24. Networking
Cisco usNIC driver
Cisco Unified Communication Manager (UCM) servers have an optional feature to provide a Cisco
proprietary User Space Network Interface Controller (usNIC), which allows performing Remote D irect
Memory Access (RD MA)-like operations for user-space applications. The libusnic_verbs driver, which
is supported as a Technology Preview, makes it possible to use usNIC devices via standard
InfiniBand RD MA programming based on the Verbs API.
Cisco VIC kernel driver
The Cisco VIC Infiniband kernel driver, which is supported as a Technology Preview, allows the use
of Remote D irectory Memory Access (RD MA)-like semantics on proprietary Cisco architectures.
T rust ed Net work Connect
Trusted Network Connect, supported as a Technology Preview, is used with existing network access
control (NAC) solutions, such as TLS, 802.1X, or IPsec to integrate endpoint posture assessment;
that is, collecting an endpoint's system information (such as operating system configuration settings,
installed packages, and others, termed as integrity measurements). Trusted Network Connect is used
to verify these measurements against network access policies before allowing the endpoint to access
the network.
SR-IOV funct ionalit y in t he qlcnic driver
Support for Single-Root I/O virtualization (SR-IOV) has been added to the qlcnic driver as a
Technology Preview. Support for this functionality will be provided directly by QLogic, and customers
are encouraged to provide feedback to QLogic and Red Hat. Other functionality in the qlcnic driver
remains fully supported.
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⁠Chapt er 2 5. St orage
Chapter 25. Storage
Mult i-queue I/O scheduling for SCSI
Red Hat Enterprise Linux 7.2 includes a new multiple-queue I/O scheduling mechanism for block
devices known as blk-mq. The scsi-mq package allows the Small Computer System Interface (SCSI)
subsystem to make use of this new queuing mechanism. This functionality is provided as a
Technology Preview and is not enabled by default. To enable it, add scsi _mo d . use_bl k_mq = Y to
the kernel command line.
Improved LVM locking infrast ruct ure
l vml o ckd is a next generation locking infrastucture for LVM. It allows LVM to safely manage shared
storage from multiple hosts, using either the d l m or sanl o ck lock managers. sanl o ck allows
l vml o ckd to coordinate hosts through storage-based locking, without the need for an entire cluster
infrastructure. For more information, see the l vml o ckd (8) man page.
T arget d plug-in from t he libSt orageMgmt API
Since Red Hat Enterprise Linux 7.1, storage array management with libStorageMgmt, a storage array
independent API, has been fully supported. The provided API is stable, consistent, and allows
developers to programmatically manage different storage arrays and utilize the hardwareaccelerated features provided. System administrators can also use libStorageMgmt to manually
configure storage and to automate storage management tasks with the included command-line
interface.
The Targetd plug-in is not fully supported and remains a Technology Preview.
DIF/DIX
D IF/D IX is a new addition to the SCSI Standard. It is fully supported in Red Hat Enterprise Linux 7.2
for the HBAs and storage arrays specified in the Features chapter, but it remains in Technology
Preview for all other HBAs and storage arrays.
D IF/D IX increases the size of the commonly used 512 byte disk block from 512 to 520 bytes, adding
the D ata Integrity Field (D IF). The D IF stores a checksum value for the data block that is calculated
by the Host Bus Adapter (HBA) when a write occurs. The storage device then confirms the checksum
on receipt, and stores both the data and the checksum. Conversely, when a read occurs, the
checksum can be verified by the storage device, and by the receiving HBA.
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7 .2 Release Not es
Chapter 26. Virtualization
Nest ed virt ualiz at ion
As a Technology Preview, Red Hat Enterprise Linux 7.2 offers nested virtualization. This feature
enables KVM to launch guests that can act as hypervisors and create their own guests.
T he virt -p2v t ool
Red Hat Enterprise Linux 7.2 offers the virt-p2v tool as a Technology Preview. virt-p2v (physical to
virtual) is a CD -ROM, ISO or PXE image that the user can boot on a physical machine, and that
creates a KVM virtual machine with disk contents identical to the physical machine.
USB 3.0 support for KVM guest s
USB 3.0 host adapter (xHCI) emulation for KVM guests remains a Technology Preview in Red Hat
Enterprise Linux 7.2.
Virt IO-1 support
Virtio drivers have been updated to Kernel 4.1 to provide VirtIO 1.0 D evice Support.
62
⁠P art III. Device Drivers
⁠Part III. Device Drivers
This part provides a comprehensive listing of all device drivers which were updated in Red Hat
Enterprise Linux 7.2.
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7 .2 Release Not es
Chapter 27. Storage Driver Updates
The hpsa driver has been updated to version 3.4.4-1-RH4.
The qla2xxx driver has been updated to version 8.07.00.18.07.2-k.
The lpfc driver has been updated to version 10.7.0.1.
The megaraid_sas driver has been updated to version 06.807.10.00.
The fnic driver has been updated to version 1.6.0.17.
The mpt2sas driver has been updated to version 20.100.00.00.
The mpt3sas driver has been updated to version 9.100.00.00.
The Emulex be2iscsi driver has been updated to version 10.6.0.0r.
The aacraid driver has been updated to version 1.2.
The bnx2i driver has been updated to version 2.7.10.1.
The bnx2fc driver has been updated to version 2.4.2.
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⁠Chapt er 2 8 . Net work Driver Updat es
Chapter 28. Network Driver Updates
The tg3 driver has been updated to version 3.137.
The e1000 driver has been updated to version 7.3.21-k8-NAPI, which provides support for txtd
update delay when using the xmit_more Boolean variable.
The e1000e driver has been updated to version 3.2.5-k.
The igb driver has been updated to version 5.2.15-k.
The igbvf driver has been updated to version 2.0.2-k.
The ixgbevf driver has been updated to version 2.12.1-k.
The ixgbe driver has been updated to version 4.0.1-k.
The bna driver and firmware have been updated to version 3.2.23.0r.
The bnx2 driver has been updated to version 2.2.6.
The CNIC driver has been updated to version 2.5.21.
The bnx2x driver has been updated to version 1.710.51-0, which also adds qlogic NPAR support
for qlogic-nx2 adapters.
The be2net driver has been updated to version 10.6.0.3r.
The qlcnic driver has been updated to version 5.3.62.
The qlge driver has been updated to version 1.00.00.34. It fixes a race condition between the New
API (NAPI) registration and unregistration which previously led to the system crash. This race
condition occured if certain parameters were changed while the Network Interface Card (NIC) was
set to " down" .
The r8169 driver has been updated to version 2.3LK-NAPI.
The i40e driver has been updated to version 1.3.21-k.
The i40evf driver has been updated to version 1.3.13.
The netxen_nic driver has been updated to version 4.0.82.
The sfc driver has been updated to the latest upstream version.
This update adds the fm10k driver of version 0.15.2-k.
This update adds VTI6 support including netns capabilities.
The bonding driver has been updated to version 3.7.1.
The iwlwifi driver has been updated to the latest upstream version.
The vxlan driver has been updated to version 0.1.
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7 .2 Release Not es
Chapter 29. Graphics Driver and Miscellaneous Driver Updates
The HD A driver has been updated to the latest upstream version to use the new jack kctls method.
The HPI driver has been updated to version 4.14.
The Realtek HD -audio codec driver has been updated to include the update of EAPD init codes.
The IPMI driver has been updated to replace the timespec usage by timespec64.
The i915 driver has been updated to include the rebase of ACPI Video Extensions driver in Red
Hat Enterprise Linux 7.2.
The ACPI Fan driver has been updated to version 0.25.
The Update NVM-Express driver has been updated to version 3.19.
The rtsx driver has been updated to version 4.0 to support rtl8402, rts524A, rts525A chips.
The Generic WorkQueue Engine device driver has been updated to the latest upstream version.
The PCI driver has been updated to version 3.16.
The ED AC kernel module has been updated to provide support for Intel Xeon v4 processors.
The pstate driver has been updated to support 6th Generation Intel Core processor.
The intel_idle driver has been updated to support 6th Generation Intel Core processor.
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⁠Chapt er 30 . Deprecat ed Funct ionalit y
Chapter 30. Deprecated Functionality
This chapter provides an overview of functionality that has been deprecated in all minor releases of
Red Hat Enterprise Linux 7 up to Red Hat Enterprise Linux 7.2.
D eprecated functionality continues to be supported until the end of life of Red Hat Enterprise Linux 7.
D eprecated functionality will likely not be supported in future major releases of this product and is
not recommended for new deployments. For the most recent list of deprecated functionality within a
particular major release, refer to the latest version of release documentation.
D eprecated hardware components are not recommended for new deployments on the current or future
major releases. Hardware driver updates are limited to security and critical fixes only. Red Hat
recommends replacing this hardware as soon as reasonably feasible.
A package can be deprecated and not recommended for further use. Under certain circumstances, a
package can be removed from a product. Product documentation then identifies more recent
packages that offer functionality similar, identical, or more advanced to the one deprecated, and
provides further recommendations.
Windows guest virt ual machine support limit ed
As of Red Hat Enterprise Linux 7, Windows guest virtual machines are supported only under specific
subscription programs, such as Advanced Mission Critical (AMC).
Deprecat ed Device Drivers
3w-9xxx
3w-sas
mptbase
mptctl
mptsas
mptscsih
mptspi
qla3xxx
The following controllers from the meg arai d _sas driver have been deprecated:
D ell PERC5, PCI ID 0x15
SAS1078R, PCI ID 0x60
SAS1078D E, PCI ID 0x7C
SAS1064R, PCI ID 0x411
VERD E_Z CR, PCI ID 0x413
SAS1078GEN2, PCI ID 0x78
The following Ethernet adapter controlled by the be2net driver has been deprecated:
TIGERSHARK NIC, PCI ID 0x0700
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The following controllers from the be2i scsi driver have been deprecated:
Emulex OneConnect 10Gb iSCSI Initiator (generic), PCI ID 0x212
OCe10101, OCm10101, OCe10102, OCm10102 BE2 adapter family, PCI ID 0x702
OCe10100 BE2 adapter family, PCI ID 0x703
The following Emulex boards from the l pfc driver have been deprecated:
⁠B lad eEn g in e 2 ( B E2) D evices
TIGERSHARK FCOE, PCI ID 0x0704
⁠F ib re C h an n el ( FC ) D evices
FIREFLY, PCI ID 0x1ae5
PROTEUS_VF, PCI ID 0xe100
BALIUS, PCI ID 0xe131
PROTEUS_PF, PCI ID 0xe180
RFLY, PCI ID 0xf095
PFLY, PCI ID 0xf098
LP101, PCI ID 0xf0a1
TFLY, PCI ID 0xf0a5
BSMB, PCI ID 0xf0d1
BMID , PCI ID 0xf0d5
Z SMB, PCI ID 0xf0e1
Z MID , PCI ID 0xf0e5
NEPTUNE, PCI ID 0xf0f5
NEPTUNE_SCSP, PCI ID 0xf0f6
NEPTUNE_D CSP, PCI ID 0xf0f7
FALCON, PCI ID 0xf180
SUPERFLY, PCI ID 0xf700
D RAGONFLY, PCI ID 0xf800
CENTAUR, PCI ID 0xf900
PEGASUS, PCI ID 0xf980
THOR, PCI ID 0xfa00
VIPER, PCI ID 0xfb00
LP10000S, PCI ID 0xfc00
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⁠Chapt er 30 . Deprecat ed Funct ionalit y
LP11000S, PCI ID 0xfc10
LPE11000S, PCI ID 0xfc20
PROTEUS_S, PCI ID 0xfc50
HELIOS, PCI ID 0xfd00
HELIOS_SCSP, PCI ID 0xfd11
HELIOS_D CSP, PCI ID 0xfd12
Z EPHYR, PCI ID 0xfe00
HORNET, PCI ID 0xfe05
Z EPHYR_SCSP, PCI ID 0xfe11
Z EPHYR_D CSP, PCI ID 0xfe12
To check the PCI ID s of the hardware on your system, run the l spci -nn command.
Note that other controllers from the mentioned drivers that are not listed here remain unchanged.
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⁠Part IV. Known Issues
This part documents known problems in Red Hat Enterprise Linux 7.2.
70
⁠Chapt er 31 . G eneral Updat es
Chapter 31. General Updates
T he T AB key does not expand $ PWD by default
When working in CLI in Red Hat Enterprise Linux 6, pressing the TAB key expanded $P WD / to the
current directory. In Red Hat Enterprise Linux 7, CLI does not have the same behavior. Users can
achieve this behavior by putting the following lines into the $HOME/.bash_profile file:
if ((BASH_VERSINFO[0] >= 4)) & & ((BASH_VERSINFO[1] >= 2)); then
shopt -s direxpand
fi
Upgrading from Red Hat Ent erprise Linux 6 may fail on IBM Power Syst ems
Because of a bug in the yabo o t boot loader, upgrading from Red Hat Enterprise Linux 6 to Red Hat
Enterprise Linux 7 can fail on IBM Power Systems servers with an Unkno wn o r co rrupt
fi l esystem error.
This problem is typically caused by a misplaced yabo o t. co nf configuration file. Make sure that
this file exists, that it is valid, and that it is placed on a standard (non-LVM) /boot partition.
T he /et c/os-release file cont ains out dat ed informat ion aft er syst em upgrade
Upgrading to the next minor release (for example, from Red Hat Enterprise Linux 7.1 to 7.2) does not
update the /etc/o s-rel ease file with the new product number. Instead, this file continues to list the
previous release number, and a new file named o s-rel ease. rpmnew is placed in the /etc
directory.
If you require the /etc/o s-rel ease file to be up-to-date, replace it with /etc/o srel ease. rpmnew.
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Chapter 32. Authentication and Interoperability
Kerberos t icket request s are refused for short lifet imes
D ue to a bug in Active D irectory, Kerberos ticket requests for short (generally below three minutes)
lifetimes, are refused. To work around this problem, request longer-lived (above five minutes) tickets
instead.
Replicat ion from a Red Hat Ent erprise Linux 7 machine t o a Red Hat
Ent erprise Linux 6 machine fails
Currently, the Camellia Kerberos encryption types (enctypes) are included as possible default
enctypes in the krb5, krb5-libs, krb5-server packages. As a consequence, replication from a Red Hat
Enterprise Linux 7 machine to a Red Hat Enterprise Linux 6 machine fails with an error message. To
work around this problem, use the default enctype controls, or tell kadmin or ipa-getkeytab which
encryption types to use.
A harmless error message is logged on SSSD st art up
If SSSD is connected to an IdM server that does not have a trust relationship established with an AD
server, the following harmless error message is printed to the SSSD domain log on startup:
Internal Error (Memory buffer error)
To prevent the harmless error message from occurring, set subd o mai ns_pro vi d er to no ne in the
sssd.conf file if the environment does not expect setting any trusted domains.
DNS z ones wit h recent ly generat ed DNSSEC keys are not signed properly
IdM does not properly sign D NS zones with recently generated D NS Security Extensions (D NSSEC)
keys. The named-pkcs11 service logs the following error in this situation:
The attribute does not exist: 0x00000002
The bug is caused by a race condition error in the D NSSEC key generation and distribution process.
The race condition prevents named-pkcs11 from accessing new D NSSEC keys.
To work around this problem, restart named-pkcs11 on the affected server. After the restart, the D NS
zone is properly signed. Note that the bug might reappear after the D NSSEC keys are changed
again.
T he old realmd version is st art ed when updat ing realmd while it is running
The real md daemon starts only when requested, then performs a given action, and after some time it
times out. When real md is updated while it is still running, the old version of real md starts upon a
next request because real md is not restarted after the update. To work around this problem, make
sure that reaml d is not running before updating it.
ipa-server-inst all and ipa-replica-inst all do not validat e t heir opt ions
The i pa-server-i nstal l and i pa-repl i ca-i nstal l utilities do currently not validate the
options supplied to them. If the user passes incorrect values to the utilities, the installation fails. To
work around the problem, make sure to supply correct values, and then run the utilities again.
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⁠Chapt er 32 . Aut hent icat ion and Int eroperabilit y
Upgrading t he ipa packages fails if t he required openssl version is not
inst alled
When the user attempts to upgrade the i pa packages, Identity Management (IdM) does not
automatically install the required version of the o penssl packages. Consequently, if the 1.0.1e-42
version of o penssl is not installed before the user runs the yum upd ate i pa* command, the
upgrade fails during the D NSKeySync service configuration.
To work around this problem, update o penssl manually to version 1.0.1e-42 or later before
updating i pa. This prevents the upgrade failure.
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7 .2 Release Not es
Chapter 33. Compiler and Tools
Mult iple bugs when boot ing from SAN over FCoE
Multiple bugs have arisen from the current implementation of boot from Storage Area Network (SAN)
using Fibre Channel over Ethernet (FCoE). Red Hat is targeting a future release of Red Hat Enterprise
Linux 7 for the fixes for these bugs. For a list of the affected bugs and workarounds (where available),
please contact your Red Hat support representative.
Valgrind cannot run programs built against an earlier version of Open MPI
Red Hat Enterprise Linux 7.2 supports only the Open MPI application binary interface (ABI) in version
1.10, which is incompatible with the previously shipped 1.6 version of the Open MPI ABI. As a
consequence, programs that are built against the earlier version of Open MPI cannot be run under
Valgrind included in Red Hat Enterprise Linux 7.2. To work around this problem, use the Red Hat
D eveloper Toolset version of Valgrind for programs linked against Open MPI version 1.6.
Synt het ic funct ions generat ed by GCC confuse Syst emT ap
A GCC optimization can generate synthetic functions for partially inlined copies of other functions.
These synthetic functions look like first-class functions and confuse tools such as SystemTap and
GD B because SystemTap probes can be placed on both synthetic and real function entry points.
This can result in multiple SystemTap probe hits per a single underlying function call.
To work around this problem, a SystemTap script may need to adopt countermeasures, such as
detecting recursion and suppressing probes related to inlined partial functions. For example, the
following script:
probe kernel.function(" can_nice" ).call { }
could attempt to avoid the described problem as follows:
global in_can_nice% probe kernel.function(" can_nice" ).call { in_can_nice[tid()] ++; if
(in_can_nice[tid()] > 1) { next } /* real probe handler here */ } probe kernel.function(" can_nice" ).return {
in_can_nice[tid()] --; }
Note that this script does not take into account all possible scenarios. It would not work as expected
in case of, for example, missed kprobes or kretprobes, or genuine intended recursion.
SELinux AVC generat ed when ABRT collect s backt races
If the new, optional ABRT feature that allows collecting backtraces from crashed processes without
the need to write a core-dump file to disk is enabled (using the C reateC o reBacktrace option in the
/etc/abrt/pl ug i ns/C C pp. co nf configuration file), an SELinux AVC message is generated when
the abrt-ho o k-ccpp tool tries to use the si g chl d access on a crashing process in order to get
the list of functions on the process' stack.
GDB keeps wat chpoint s act ive even aft er report ing t hem as hit
In some cases, on the 64-bit ARM architecture, GD B can incorrectly keep watchpoints active even
after reporting them as hit. This results in the watchpoints getting hit for the second time, only this
time the hardware indication is no longer recognized as a watchpoint and is printed as a generic
SIGTRAP signal instead. There are several ways to work around this problem and stop the excessive
SIGTRAP reporting.
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⁠Chapt er 33. Compiler and T ools
* Type co nti nue when seeing a SIGTRAP after a watchpoint has been hit.
* Instruct GD B to ignore the SIGTRAP signal by adding the following line to your ~ /. g d bi ni t
configuration file:
handle SIGTRAP nostop noprint
* Use software watchpoints instead of their hardware equivalents. Note that the debugging is
significantly slower with software watchpoints, and only the watch command is available (not
rwatch or awatch). Add the following line to your ~ /. g d bi ni t configuration file:
set can-use-hw-watchpoints 0
Boot ing fails using grubaa64 .efi
D ue to issues in pxeboot or the PXE configuration file, installing Red Hat Enterprise Linux 7.2 using
the 7.2 grubaa64.efi boot loader either fails or experiences significant delay in booting the operating
system. As a workaround, use the 7.1 grubaa64.efi file instead of the 7.2 grubaa64.efi file when
installing Red Hat Enterprise Linux 7.2.
MPX feat ure in GCC requires Red Hat Developer T oolset version of t he libmpx
library
The libmpxwrappers library is missing in the gcc-libraries version of the libmpx library. As a
consequence, the Memory Protection Extensions (MPX) feature might not work correctly in GCC, and
the application might not link properly. To work around this problem, use the Red Hat D eveloper
Toolset 4.0 version of the libmpx library.
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7 .2 Release Not es
Chapter 34. Desktop
Broken pygobject 3 package dependencies prevent upgrade from Red Hat
Ent erprise Linux 7.1
The pygobject3-devel.i686 32-bit package has been removed in Red Hat Enterprise Linux 7.2 and was
replaced with a multilib version. If you have the 32-bit version of the package installed on a Red Hat
Enterprise Linux 7.1 system, then you will encounter a yum error when attempting to upgrade to Red
Hat Enterprise Linux 7.2.
To work around this problem, use the yum remo ve pyg o bject3-d evel . i 6 86 command as ro o t
to uninstall the 32-bit version of the package before upgrading your system.
Build requirement s not defined correct ly for Emacs
The binutils package earlier than version 2.23.52.0.1-54 causes a segmentation fault during the build.
As a consequence, it is not possible to build the Emacs text editor on IBM Power Systems. To work
around this problem, install the latest binutils.
Ext ernal display issues when combining lapt op un/dock and suspend
In the GNOME desktop environment, with some laptops, external displays connected to a docking
station might not be automatically activated when resuming a suspended laptop after it has been
undocked and docked again.
To work around this problem, open the D isplays configuration panel or run the xrand r command in
a terminal. This makes the external displays available again.
Emacs somet imes t erminat es unexpect edly when using t he up arrow on ARM
On the ARM architecture, the Emacs text editor sometimes terminates unexpectedly with a
segmentation fault when scrolling up a file buffer. This happens only when the syntax highlighting is
enabled. There is not currently any known workaround for this problem.
76
⁠Chapt er 35. Inst allat ion and Boot ing
Chapter 35. Installation and Booting
Inst allat ion fails wit h a t raceback when specifying % packages --nobase -nocore in a Kickst art file
Using a Kickstart file which contains the %packag es section and specifies the --no base and -no co re options at the same time causes the installation to fail with a traceback message due to the
yum-langpacks package missing.
To work around this problem, add the yum-langpacks package within the %packag es section when
using %packag es --no base --no co re in your Kickstart file.
Inst allat ion can not proceed if a root password specified in Kickst art does
not pass policy requirement s
If you use a Kickstart file that defines a root password and the password does not fullfill requirements
for the security policy selected in the Security Policy spoke, you will be unable to complete the
installation. The Beg i n Instal l ati o n button will be grayed out, and it is not possible to change
the root password manually before pressing this button.
To work around this problem, make sure that your Kickstart file uses a sufficiently strong password
that passes requirements defined by the selected security policy.
Rescue mode fails t o det ect and mount root volume on Bt rfs
The installer rescue mode (accessed from the installation media boot menu or using the
i nst. rescue boot option) can not detect an existing system with the / (root) directory placed on a
Btrfs subvolume. Instead, an error message saying 'You don't have any linux partitions.' is
displayed.
To work around this problem, enter the shell and mount the root volume manually.
Wrong window t it le in Init ial Set up
The Initial Setup tool, which is automatically displayed after the first post-installation reboot and
which allows you to configure settings like network connections and to register your system, displays
the string __mai n__. py in the window title.
This is a cosmetic problem and has no negative impact on usability.
Reinst alling on an FBA DASD on IBM Syst em z causes t he inst aller t o crash
When reinstalling Red Hat Enterprise Linux 7 on IBM System z with a Fixed Block Architecture (FBA)
D ASD , the installer will crash due to incomplete support for these devices.
To work around this problem, ensure that any FBA D ASD s are not present during the installation by
placing them on the device ignore list. This should be done before launching the installer. From a
root shell, use the chccwd ev command followed by the ci o _i g no re command to manually switch
devices offline and then add them to the device ignore list.
Alternatively, you can remove all FBA D ASD device ID s from the CMS configuration file or the
parameter file instead of using these commands before beginning the installation.
HyperPAV aliases are not available aft er inst allat ion on IBM Syst em z
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7 .2 Release Not es
A known issue prevents D ASD s configured as HyperPAV aliases from being automatically attached
to the system after the installation finishes. These storage devices are available at the Installation
D estination screen during installation, but they are not immediately accessible after you finish
installing and reboot.
To fix this problem temporarily (until the next reboot), remove these devices from the device blacklist
using the chccwd ev command:
# chccwd ev -e <d evnumber>
To make the HyperPAV aliases available persistently across reboots, add their device numbers into
the /etc/d asd . co nf configuration file.
You can use the l sd asd command to verify that these devices are available.
Generat ed anaconda-ks.cfg file on IBM Syst em z can not be used t o reinst all
t he syst em
The anaco nd a-ks. cfg file, which is a Kickstart file generated during system installation and which
contains all selections made during the install process, represents disk sizes as decimal numbers on
IBM System z D ASD s. This is because D ASD s report a 4KiB alignment, which makes the calculated
disk sizes incorrect as they are recorded in the Kickstart file, since only integer values are accepted.
Therefore, it is not possible to re-use the generated Kickstart file to reproduce the installation.
Using the anaco nd a-ks. cfg file on IBM System z to reinstall the system requires you to manually
change all decimal values within to integers.
Possible Net workManager error message during inst allat ion
When installing the system, the following error message can be displayed and logged:
ERR NetworkManager: <error> [devices/nm-device.c:2590] activation_source_schedule(): (eth0):
activation stage already scheduled
The error message should not prevent the installation from completing.
Package libocrdma is missing from t he InfiniBand Support package group
The libocrdma package is not included in the default package set of the InfiniBand Support group.
Consequently, when users select the InfiniBand Support group and are expecting RD MA over
Converged Ethernet (RoCE) to work on Emulex OneConnect adapters, the necessary driver, libocrdma,
is not installed by default.
On first boot, the user can manually install the missing package by issuing this command:
# yum i nstal l l i bo crd ma
Alternatively, add the libocrdma package to the %packag es section of your Kickstart file.
As a result, the user will now be able to use the Emulex OneConnect devices in RoCE mode.
Insufficient siz e of t he /boot part it ion may prevent t he syst em from
upgrading
78
⁠Chapt er 35. Inst allat ion and Boot ing
The /boot partition, which contains installed kernels and initial ram disks, may become full if multiple
kernels and additional packages such as kernel-debug are installed. This is caused by the default
size of this partition being set to 500 MB during installation, and prevents the system from being
upgraded.
As a workaround, use yum to remove older kernels if you do not need them. If you are installing a new
system, you should also consider this possibility, and set the /boot partition to a larger size (for
example 1 GB) instead of the default (500 MB).
Inst allat ion on mult ipat h devices fails if one or more disks are missing a label
When installing on multipath devices, the installer may display an error dialog if it fails to read one or
more disks which are a member of the multipath. This problem is caused by one or more disks
missing a disk label, and the installation can not proceed if it occurs.
To work around this problem, create disk labels on all disks which are part of the multipath device
you are using during the installation.
St at ic IPv4 configurat ion in Kickst art is overwrit t en if a host name is defined
in % pre script
When defining a host name in the %pre section of a Kickstart file, a netwo rk command that only sets
host name (" network --hostname=hn" ) is considered as a device configuration with default -bootproto value (" dhcp" ) and default --d evi ce value (" link" , which means the first device with link
found). The Kickstart then behaves as if netwo rk --ho stname= hn --d evi ce= l i nk was used.
If the device considered as default for the --d evi ce option (the first device with link found) has
already been configured to use static IPv4 configuration (for example with the preceding netwo rk
command), the configuration is overriden by the IPv4 D HCP implied by the --ho stname option.
To work around this problem, make sure that the netwo rk command which defines the host name is
used first, and the second netwo rk command which would normally be overridden is used
afterwards.
In cases where the netwo rk command defining a host name is the only such command in the
Kickstart file, add a --d evi ce option to it with a non-existing interface (for example, netwo rk -ho stname= hn --d evi ce= x).
Using t he realm command in Kickst art causes t he inst aller t o crash
A known issue prevents the real m command from being used in Kickstart files. Attempting to join an
Active D irectory or Identity Management domain during the installation using this command causes
the installer to crash.
To work around this problem, you can either wait until the installation finishes and join a domain
manually afterwards, or you can add the real m jo i n <real m name> command to the Kickstart
file's %po st section. See the real m(8) man page for information joining a domain using the
command line.
Inst aller built -in help is not updat ed during syst em upgrade
When upgrading from Red Hat Enterprise Linux 7.1 to version 7.2, the built-in help for the Anaconda
installer (the anaconda-user-help package) is not upgraded due to a significant change in packaging.
To work around this problem, use yum to remove the anaconda-user-help package before performing
the upgrade, and install it again after you finish upgrading to Red Hat Enterprise Linux 7.2.
79
7 .2 Release Not es
Incorrect ordering of boot menu ent ries generat ed by grubby
The g rubby tool, which is used to modify and update the GRUB2 boot loader configuration files,
may add debug boot menu entries at the top of the list when generating the boot menu configuration
file. These debug menu entries then cause normal entries to be pushed down, although they are still
highlighted and selected by default.
Using mult iple driver updat e images at t he same t ime only applies t he last
one specified
When attempting to perform a driver update during the installation using the i nst. d d = /d d . i mg
boot option and specifying it more than once to load multiple driver update images, Anaconda will
ignore all instances of the parameter except the last one.
To work around this problem, you can:
* Install additional drivers after the installation if possible
* Use alternate means to specify a driver update image, such as the d ri verd i sk Kickstart command
* Combine multiple driver update images into a single one
Inst aller crashes when it det ect s LDL-format t ed DASDs
The installer crashes whenever it detects the LD L (Linux D isk Layout) format on one or more D ASD s
on IBM System z. The crash is caused by a race condition in the l i bparted library and happens
even if these D ASD s are not selected as installation targets. Other architectures are not affected by
this issue.
If LD L D ASD s are to be used during installation, users should manually reformat each LD L D ASD as
CD L (Compatible D isk Layout) using the d asd fmt command in a root shell before launching the
installer.
If LD L D ASD s are present on a system and a user does not wish to utilize them during installation,
they should be placed on the device ignore list for the duration of the installation process. This
should be done before launching the installer. From a root shell, users should use the chccwd ev
command followed by the ci o _i g no re command to manually switch devices offline and then add
them to the device ignore list.
Alternatively, you can remove all LD L D ASD device ID s from the CMS configuration file or the
parameter file instead of using these commands before beginning the installation.
Kernel panic on reboot aft er upgrading kernel and redhat -release packages
Installing redhat-release-server-7.2-9.el7 and a kernel package in the same Yum transaction leads to a
missing i ni trd line in the new kernel's menu entry in GRUB2 configuration. Attempting to boot
using the latest installed kernel then causes a kernel panic due to missing initrd. This issue usually
appears while upgrading your system from an earlier minor release to Red Hat Enterprise Linux 7.2
using yum upd ate.
To work around this problem, make sure to upgrade the redhat-release-server and kernel packages in
separate Yum transactions. Alternatively, you can locate the new kernel's menu entry in the GRUB2
configuration file (/bo o t/g rub2/g rub. cfg on BIOS systems and
/bo o t/efi /EFI/red hat/g rub. cfg on UEFI systems) and add the initrd manually.
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⁠Chapt er 35. Inst allat ion and Boot ing
The initrd configuration line will look similar to i ni trd /i ni tramfs-3. 10 . 0 327. el 7. x86 _6 4 . i mg . Make sure the file name matches the kernel (vmlinuz) configured within the
same menu entry and that the file exists /bo o t directory. Use older menu entries for reference.
Init ial Set up may st art in t ext mode even if a graphical environment is
inst alled
The Initial Setup utility, which starts after installation finishes and the installed system is booted for
the first time, may in some cases start in text mode on systems where a graphical environment is
available and the graphical version of Initial Setup should start. This is caused by both the
graphical and text mode services for Initial Setup being enabled at the same time.
To work around this problem, you can use a Kickstart file during the installation and include a
%po st section to disable the version of Initial Setup which you do not want to run.
To make sure that the graphical variant of Initial Setup runs after installation, use the following
%po st section:
%post
systemctl disable initial-setup-text.service
systemctl enable initial-setup-graphical.service
%end
If you want to enable the text mode variant of Initial Setup, switch the enabl e and d i sabl e
commands in order to disable the graphical service and enable text mode.
Links t o non-root file syst ems in /l i b/ and /l i b6 4 / are removed by
l d co nfi g . servi ce
Red Hat Enterprise Linux 7.2 introduced l d co nfi g . servi ce, which is run at an early stage of the
boot process, before non-root file systems are mounted. When l d co nfi g . servi ce is run, links in
the /l i b/ and /l i b6 4 / directories are removed if they point to file systems which are not yet
mounted. To work around this problem, disable l d co nfi g . servi ce with the command
systemctl mask l d co nfi g , so these symbolic links are no longer removed, and the system
boots as expected.
Daemons using IPC t erminat e unexpect edly aft er updat e t o Red Hat
Ent erprise Linux 7.2
A new systemd feature was introduced in Red Hat Enterprise Linux 7.2: cleanup of all allocated interprocess communication (IPC) resources with the last session a user finishes. A session can be an
administrative cro n job or an interactive session. This behavior can cause daemons running under
the same user, and using the same resources, to terminate unexpectedly. To work around this
problem, edit the file /etc/systemd /l o g i nd . co nf and add the following line:
RemoveIPC=no
Then, execute the following command, so that the change is put into effect:
systemctl restart systemd-logind.service
After performing these steps, daemons no longer crash in the described situation.
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7 .2 Release Not es
Chapter 36. Kernel
Some ext 4 file syst ems cannot be resiz ed
D ue to a bug in the ext4 code, it is currently impossible to resize ext4 file systems that have 1 kilobyte
block size and are smaller than 32 megabytes.
Repeat ed connect ion loss wit h iSER-enabled iSCSI t arget s
When using the server as an iSER-enabled iSCSI target, connection losses occur repeatedly, the
target can stop responding and the kernel becomes unresponsive. To work around this issue,
minimize iSER connection losses or revert to non-iSER iSCSI mode.
Inst aller does not det ect Fibre Channel over Et hernet disks on EDD syst ems
On ED D systems, FCoE disks are not detected automatically by Anaconda due to the ed d driver
missing. This makes such disks unusable during the installation.
To work around this problem, perform the following steps:
* Add fco e= ed d : no d cb to the kernel command line during the installation, the FCoE disks will be
detected by anaconda.
* Add fco e= ed d : no d cb to the rescue image and boot the system with it.
* Add the edd module to the initrd image by executing the following commands:
#d racut --reg enerate-al l -f
#d racut --ad d -d ri vers ed d /bo o t/i ni tramfs-3. 10 . 0 -123. el 7. x86 _6 4 . i mg
* Reboot the system with the default boot menu entry
NUMA balancing does not work opt imally under cert ain circumst ances
The Linux kernel Non-Uniform Memory Access (NUMA) balancing does not work optimally under the
following condition in Red Hat Enterprise Linux 7. When the numa_bal anci ng option is set, some of
the memory can move to an arbitrary non-destination node before moving to the constrained nodes,
and the memory on the destination node also decreases under certain circumstances. There is
currently no known workaround available.
PSM2 MT L disabled t o avoid conflict s bet ween PSM and PSM2 APIs
The new libpsm2 package provides the PSM2 API for use with Intel Omni-Path devices, which
overlaps with the Performance Scaled Messaging (PSM) API installed by the infinipath-psm package
for use with Truescale devices. The API overlap results in undefined behavior when a process links
to libraries provided by both packages. This problem affects O pen MP I if the set of its enabled MCA
modules includes the psm2 Matching Transport Layer (MTL) and one or more modules that directly or
indirectly depend on the l i bpsm_i nfi ni path. so . 1 library from the infinipath-psm package.
To avoid the PSM and PSM2 API conflict, Open MPI's psm2 MTL has been disabled by default in the
/etc/o penmpi -*/o penmpi -mca-params. co nf configuration file. If you enable it, you need to
disable the psm and o fi MTLs and the usni c Byte Transfer Layer (BTL) that conflict with it
(instructions are also provided in comments in the configuration file).
There is also a packaging conflict between the libpsm2-compat-devel and infinipath-psm-devel
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⁠Chapt er 36 . Kernel
packages because they both contain PSM header files. Therefore, the two packages cannot be
installed at the same time. To install one, uninstall the other.
Performance problem of t he perf ut ilit y
The perf archi ve command, which creates archives with object files with build ID s found in
perf. d ata files, takes a long time to complete on IBM System z. At present, no known workaround
exists. Other architectures are not affected.
qlcnic fails t o enslaved by bonding
Certain bonding modes set a MAC address on the device which the qlcnic driver does not properly
recognize. This prevents the device from restoring its original MAC address when it is removed from
the bond.
As a workaround, unenslave the qlcnic driver and reboot your operating system.
Inst allat ion fails on some 64 -bit ARM Applied Micro comput ers
Red Hat Enterprise Linux 7.2 fails to install on certain 64-bit ARM systems by Applied Micro with the
following error message:
Unabl e to hand l e kernel NULL po i nter d ereference at vi rtual ad d ress
0 0 0 0 0 33f
At present, there is no workaround for this problem.
l i bvi rt management of VFIO devices can lead t o host crashes
The l i bvi rt management of host PCI devices, assigned to guests using the VFIO driver, can lead
to host kernel drivers and the vfio-pci driver binding simultaneously to devices in the same IOMMU
group. This is an invalid state, which can lead to a host unexpected termination.
For now, the only workaround is to never hot-unplug a VFIO device from a guest, if there are any
other devices in the same IOMMU group.
Inst allat ion using iSCSI and IPv6 hangs for 15 minut es
D racut times out after trying to connect to the specified iSCSI server for 15 minutes if IPv6 is enabled.
Eventually, D racut connects successfully and proceeds as expected; however, to avoid the delay,
use i p= eth0 : auto 6 on the installer's command line.
i4 0e NIC freez e
With old firmware, a network card using the i40e driver becomes unusable for about ten seconds after
it enters the promiscuous mode. To avoid this problem, update the firmware.
i4 0e is issuing WARN_ON
The i40e driver is issuing the WARN_ON macro during ring size changes because the code is
cloning the rx_ring struct but not zeroing out the pointers before allocating new memory. Note that
this warning is harmless to your system.
net prio_cgroups not mount ed at boot
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7 .2 Release Not es
Currently, systemd mounts the /sys/fs/cgroup/ directory as read-only, which prevents the default
mount of the /sys/fs/cgroup/net_prio/ directory. As a consequence, the netprio_cgroups module is not
mounted at boot. To work around this problem, use the mo unt -o remo unt command, followed by
rw -t cg ro up no d ev /sys/fs/cg ro ups. This makes it possible to install module-based
cgroups manually.
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⁠Chapt er 37 . Net working
Chapter 37. Networking
T imeout policy not enabled in Red Hat Ent erprise Linux 7.2 kernel
The nfct ti meo ut command is not supported in Red Hat Enterprise Linux 7.2. As a workaround,
use the global timeout values available at
/pro c/sys/net/netfi l ter/nf_co nntrack_*_ti meo ut_* to set the timeout value.
Verificat ion of signat ures using t he MD5 hash algorit hm is disabled in Red
Hat Ent erprise Linux 7
It is not possible to connect to any Wi-Fi Protected Access (WPA) Enterprise Access Point (AP) that
requires MD 5-signed certificates. To work around this problem, copy the
wpa_suppl i cant. servi ce file from the /usr/l i b/systemd /system/ directory to the
/etc/systemd /system/ directory and add the following line to the Servi ce section of the file:
Environment=OPENSSL_ENABLE_MD5_VERIFY=1
Then run the systemctl d aemo n-rel o ad command as root to reload the service file.
Important
Note that MD 5 certificates are highly insecure and Red Hat does not recommend using them.
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7 .2 Release Not es
Chapter 38. Storage
No support for t hin provisioning on t op of RAID in a clust er
While RAID logical volumes and thinly provisioned logical volumes can be used in a cluster when
activated exclusively, there is currently no support for thin provisioning on top of RAID in a cluster.
This is the case even if the combination is activated exclusively. Currently this combination is only
supported in LVM's single machine non-clustered mode.
When using t hin-provisioning, it is possible t o lose buffered writ es t o t he
t hin-pool if it reaches capacit y
If a thin-pool is filled to capacity, it may be possible to lose some writes even if the pool is being
grown at that time. This is because a resize operation (even an automated one) will attempt to flush
outstanding I/O to the storage device prior to the resize being performed. Since there is no room in
the thin-pool, the I/O operations must be errored first to allow the grow to succeed. Once the thin pool
has grown, the logical volumes associated with the thin-pool will return to normal operation.
As a workaround to this problem, set 'thin_pool_autoextend_threshold' and
'thin_pool_autoextend_percent' appropriately for your needs in the lvm.conf file. D o not set the
threshold so high or the percent so low that your thin-pool will reach full capacity so quickly that it
does not allow enough time for it to be auto-extended (or manually extended if you prefer). If you are
not using over-provisioning (creating logical volumes in excess of the size of the backing thin-pool),
then be prepared to remove snapshots as necessary if the thin-pool begins to near capacity.
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⁠Chapt er 39 . Syst em and Subscript ion Management
Chapter 39. System and Subscription Management
Non-working Back but t on in t he Subscript ion Manager add-on for Init ial Set up
The Back button on the first panel of the Subscription Manager add-on for the Initial Setup utility
does not work. To work around this problem, click D o ne at the top of Initial Setup to exit the
registration workflow.
virt -who fails t o change host -t o-guest associat ion t o t he Candlepin server
When adding, removing, or migrating a guest, the virt-who utility currently fails to send the host-toguest mapping and prints a RateLimitExceededException error to the log file. To work around the
problem, set the VIR T WHO _INT ER VAL= parameter in the /etc/sysconfig/virt-who file to a large
number, such as 600. This allows the mapping to be changed correctly, but causes changes in the
host-to-guest mapping to take significantly longer to be processed.
ReaR fails t o creat e an ISO on IBM Syst em z
ReaR is unable to create an ISO image on IBM System z systems. To work around this problem, use
a different type of rescue system than ISO.
ReaR support s only grub during syst em recovery
ReaR supports only the grub boot loader. Consequently, ReaR cannot automatically recover a
system with a different boot loader. Notably, yab o o t is not yet supported by ReaR on PowerPC
machines. To work around this problem, edit the boot loader manually.
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7 .2 Release Not es
Chapter 40. Virtualization
Problemat ic GRUB 2 navigat ion wit h KVM
When using the serial console through KVM, holding down an arrow key for an extended period of
time to navigate in the GRUB 2 menu results in erratic behavior. To work around this problem, avoid
the rapid input caused by holding an arrow key down for a longer time.
Resiz ing GUID Part it ion T able (GPT ) disks on Hyper-V guest s causes
part it ion t able errors
The Hyper-V manager supports shrinking a GPT-partitioned disk on a guest if there is free space
after the last partition, by allowing the user to drop the unused last part of the disk. However, this
operation will silently delete the secondary GPT header on the disk, which may trigger error
messages when guest examines the partition table (for example, with parted(8)). This is a known limit
of Hyper-V.
To work around this, it is possible to manually restore the secondary GPT header with the gdisk(8)
expert command e, after shrinking the GPT disk. This also occurs when using Hyper-V's Expand
option, but can also be fixed with the parted(8) tool.
Bridge creat ion wit h vi rsh i face-bri d g e fails
When installing Red Hat Enterprise Linux 7 from other sources than the network, network device
names are not specified by default in the interface configuration files (this is done with a D EVIC E=
line). As a consequence, creating a network bridge by using the vi rsh i face-bri d g e command
fails with an error message. To work around the problem, add D EVIC E= lines into the
/etc/sysconfig/network-scripts/ifcfg-* files.
QEMU-emulat ed CAC smart cards incompat ible wit h Act ivClient soft ware
Currently, Common Access Card (CAC) smart cards emulated with QEMU are not accepted by
ActivClient software. To work around this problem, disable the pcscd daemon, provision a Windows
KVM guest, preconfigure it in the virt-viewer tool and select the USB redirection option, install the
ActivClient software, and reboot the KVM guest. With this setup, ActivClient accepts the emulated CAC
card.
virt io-win VFD files do not cont ain Windows 10 drivers
D ue to limitations on floppy file size, the virtual floppy disk (VFD ) files in the virtio-win packages do
not contain a Windows 10 folder. If a user needs to install Windows 10 drivers from a VFD , they can
use the Windows 8 or Windows 8.1 drivers instead. Alternatively, the Windows 10 drivers can be
installed from the ISO file in the /usr/share/virtio-win/ directory.
Migrat ed guest s do not display t he boot menu on t he serial console
Virtual machines (VMs) created on Red Hat Enterprise Linux 6 that have no graphics card (such as
VMs created using the virt-install utility with the --g raphi cs no ne option) do not show the boot
menu on the serial console anymore after migrating to Red Hat Enterprise Linux 7 hosts. To work
around this problem, add the <bios useserial='yes'/> line to the domain.xml file, which allows the
boot menu to display as expected.
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⁠Chapt er 4 0 . Virt ualiz at ion
Note that if the XML file is modified this way, it should not be used on Red Hat Enterprise Linux 6.6 or
earlier, as these do not benefit from changes introduced for BZ #1162759.
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7 .2 Release Not es
Appendix A. Component Versions
This appendix is a list of components and their versions in the Red Hat Enterprise Linux 7.2 release.
T ab le A.1. C o mp o n en t Versio n s
C o mp o n en t
Versio n
Kernel
QLogic q l a2xxx driver
QLogic q l a4 xxx driver
Emulex l pfc driver
iSCSI initiator utils
D M-Multipath
LVM
3.10.0-327
8.07.00.18.07.2-k
5.04.00.00.07.02-k0
0:10.7.0.1
iscsi-initiator-utils-6.2.0.873-32
device-mapper-multipath-0.4.9-85
lvm2-2.02.130-5
90
⁠Appendix B. Revision Hist ory
Appendix B. Revision History
R evisio n 0.0- 1.55
T u e Feb 14 2017
Updated the cifs rebase description (File Systems).
Len ka Šp ačko vá
R evisio n 0.0- 1.53
Fri O ct 21 2016
Len ka Šp ačko vá
Moved the i 4 0 e and i 4 0 evf drivers to fully supported (Networking).
R evisio n 0.0- 1.52
Fri Sep 23 2016
Len ka Šp ačko vá
Added the q l a3xxx driver to D eprecated Functionality. Added a change in behavior regarding
expanding $P WD to Known Issues.
R evisio n 0.0- 1.50
Mo n Sep 19 2016
Minor fix to the OPA kernel driver note (Technology Previews).
Len ka Šp ačko vá
R evisio n 0.0- 1.4 9
T u e Sep 13 2016
Len ka Šp ačko vá
Updated Architectures. Added new variables for d racut (New Features – Kernel). Added a note on
new o racl e profile in T u n ed (New Features – Servers and Services). Updated OverlayFS with an
XFS-related note (Technology Previews – File Systems).
R evisio n 0.0- 1.4 8
T h u Au g 04 2016
Len ka Šp ačko vá
The Atomic Host and Containers Release Notes are now separate; added a link to the new document.
R evisio n 0.0- 1.4 7
Mo n Au g 01 2016
Len ka Šp ačko vá
Added a note about limited support for Windows guest virtual machines to D eprecated Functionality.
R evisio n 0.0- 1.4 6
T h u Ju l 11 2016
Added a Known Issue for Atomic Host and Containers.
Yo an a R u seva
R evisio n 0.0- 1.4 5
Fri Ju l 08 2016
Fixed version of the q l a2xxx driver in Component Versions.
Len ka Šp ačko vá
R evisio n 0.0- 1.4 4
T h u Ju n 23 2016
Yo an a R u seva
Updated the Atomic Host and Containers chapter with the release of Red Hat Enterprise Linux Atomic
Host 7.2.5.
R evisio n 0.0- 1.4 3
Wed Ju n 22 2016
Added two known issues to Installation and Booting.
Len ka Šp ačko vá
R evisio n 0.0- 1.4 2
Mo n Ju n 13 2016
Len ka Šp ačko vá
Moved " Multiple CPU support in kd ump" from Technology Previews to fully supported New Features.
R evisio n 0.0- 1.4 1
Fri Ju n 10 2016
Added two ReaR known issues.
Len ka Šp ačko vá
R evisio n 0.0- 1.4 0
Mo n Ju n 06 2016
Len ka Šp ačko vá
Updated D eprecated Functionality. Added a bug fix in ReaR and an OpenSSL known issue, which is
valid for all Red Hat Enterprise Linux 7 minor releases.
R evisio n 0.0- 1.38
T h u May 19 2016
Yo an a R u seva
91
7 .2 Release Not es
Updated the New Features and Technology Previews chapters for Atomic Host and Containers.
R evisio n 0.0- 1.37
T h u May 12 2016
Len ka Šp ačko vá
Updated the Atomic Host and Containers chapter with the release of Red Hat Enterprise Linux Atomic
Host 7.2.4; two versions of the docker service are now available.
R evisio n 0.0- 1.36
T h u Ap r 21 2016
Len ka Šp ačko vá
Updated the Atomic Host and Containers chapter; added names of containers.
R evisio n 0.0- 1.35
Wed Ap r 13 2016
Len ka Šp ačko vá
Moved the kp at ch utility from Technology Previews to supported New Features, see details in
Chapter 10, Kernel.
R evisio n 0.0- 1.34
T h u Mar 31 2016
Len ka Šp ačko vá
Updated the Atomic Host and Containers chapter with the release of Red Hat Enterprise Linux Atomic
Host 7.2.3.
R evisio n 0.0- 1.33
Mo n Mar 28 2016
Len ka Šp ačko vá
Updated D eprecated Functionality, Technology Previews (clufter), New Features (winbindd).
R evisio n 0.0- 1.32
Mo n Feb 29 2016
Len ka Šp ačko vá
Removed information about the ato mi c ho st d epl o y sub-command, which is not available yet.
R evisio n 0.0- 1.31
T u e Feb 23 2016
Len ka Šp ačko vá
Updated the Atomic Host and Containers chapter with information on dropping support for v1beta3
API.
R evisio n 0.0- 1.30
T u e Feb 16 2016
Len ka Šp ačko vá
Updated the Atomic Host and Containers chapter with the release of Red Hat Enterprise Linux Atomic
Host 7.2.2.
R evisio n 0.0- 1.29
T h u Feb 11 2016
Len ka Šp ačko vá
Corrected the description of the RoCE Express feature for RD MA Technology Preview.
R evisio n 0.0- 1.28
T u e Jan 26 2016
Len ka Šp ačko vá
Removed incorrect information about the Ph o t o s application from New Features (D esktop).
R evisio n 0.0- 1.27
T u e Jan 19 2016
Added a known issue (Installation and Booting).
Len ka Šp ačko vá
R evisio n 0.0- 1.26
Wed Jan 13 2016
Added a bug fix regarding RMRR (Virtualization).
Len ka Šp ačko vá
R evisio n 0.0- 1.25
T h u D ec 10 2015
Added a known issue (Installation and Booting).
Len ka Šp ačko vá
R evisio n 0.0- 1.22
Wed D ec 02 2015
Added several known issues (Virtualization, Authentication).
Len ka Šp ačko vá
R evisio n 0.0- 1.21
T h u N o v 19 2015
Release of the Red Hat Enterprise Linux 7.2 Release Notes.
Len ka Šp ačko vá
92
⁠Appendix B. Revision Hist ory
R evisio n 0.0- 1.4
Mo n Au g 31 2015
Lau ra B ailey
Release of the Red Hat Enterprise Linux 7.2 Beta Release Notes.
93